Condensing Gas Package Unit Configured to Drain Condensate Through Inducer Fan and Method of Reducing Fuel Consumption

ABSTRACT

Air conditioning units packaged with condensing gas heat exchangers where condensate from the heat exchanger passes through the inducer fan, into an exhaust conduit, and out of the unit enclosure, and methods that reduce consumption of fossil fuels using air conditioning units with condensing gas heat exchangers by advertising that the units can be installed on the roof of a building or at ground level. Some embodiments include a drain hole extending through a collector attached to the heat exchanger to the inlet of the inducer fan. In some embodiments, a bifurcation in the exhaust conduit separates condensate from most combustion gasses. Some embodiments discharge condensate into a vertical standpipe in the ground that may extend below the frost line. Various methods include instructing an installer of the units regarding how to install the units and dispose of condensate into the ground or through a drain line into the building.

RELATED PATENT APPLICATIONS

This patent application is related to two other United Statesnon-provisional patent applications filed on the same day, having atleast three inventors in common, having a common assignee, and havingthe same drawings, brief description of the drawings section, anddetailed description of examples of embodiments section, but havingdifferent claims, summary of the invention sections, abstracts, andtitles. These two other patent applications are titled: “CONDENSING GASPACKAGE UNIT FOR ROOF OR GROUND INSTALLATION, COLLECTOR, AND CONDENSATEDRAIN APPARATUS” and “CONDENSING GAS PACKAGE UNIT CONFIGURED TO DRAINCONDENSATE THROUGH RETURN AIR DUCT OR FLOOR OF UNIT ENCLOSURE.” Further,to the extent not already included herein, the contents of both of theseother two patent applications are incorporated herein by reference.

FIELD OF THE INVENTION

This Invention relates to heating, ventilating, and air conditioning(HVAC) equipment and furnaces, and in particular, gas package units andcondensing furnaces.

BACKGROUND OF THE INVENTION

Heating, ventilating, and air conditioning (HVAC) equipment has beenused to heat, cool, and ventilate buildings and other enclosed spaceswhere people live and work. Air conditioning units have been used toprovide cooling in the summer months. In addition, furnaces have beenpackaged separately and with air conditioning units and the furnaceshave been operated in the winter months to provide heating. Furthermore,condensing furnaces have been used to reduce consumption of fossil fuels(e.g., natural gas or propane) burned in furnaces to provide heating.Condensing gas furnaces, however, have typically been located indoors.In such installations, condensate was typically drained into a sewer ina conventional manner. Many buildings, however, are configured to havean HVAC unit installed on the roof of the building or on the groundoutside the building. In the past, such applications have typically notpermitted use of a condensing furnace because condensate from thefurnace would freeze when local ambient temperatures were belowfreezing. Frozen condensate would interfere with continued operation ofthe unit, collect causing a hazard or nuisance, or a combinationthereof.

A number of reasons exist to reduce consumption of fossil fuels. Thesereasons may include, as examples, reducing fuel bills for the buildingowner, reducing greenhouse gas (e.g., carbon dioxide) production,reducing emissions of traditional pollutants such as carbon monoxide,hydrocarbons, and oxides of nitrogen, reducing dependency on limitedfossil fuel reserves, reducing dependency on foreign sources of fossilfuels, reducing environmental damage and risk associated with extractionof fossil fuels, and qualifying for government incentives designed toreduce consumption of fossil fuels. Since many buildings are configuredfor HVAC units that are located outdoors, conversion of outdoor gaspackage units to condensing gas package units has the potential tosignificantly reduce consumption of fossil fuels. Consequently, needs orpotential for benefit exist for equipment, apparatuses, and methods thatallow condensing gas furnaces to be installed and used outdoors. Inparticular, needs or potential for benefit exist for equipment,apparatuses, and methods that prevent problems that result from thefreezing of condensate from condensing furnaces that are installedoutdoors. Needs or potential for benefit exist for equipment,apparatuses, and methods that prevent frozen condensate from interferingwith continued operation of the HVAC unit, from collecting, from causinga hazard or nuisance, or a combination thereof, as examples.

Outdoor condensing gas furnaces have previously been contemplated andcondensate drain lines for such units have been routed to avoidfreezing. U.S. Pat. No. 6,684,878 (Ho et al.) illustrates an example.For various reasons, however, prior art outdoor condensing (e.g., gas)furnaces have not successfully been mass produced. Condensing gasfurnaces, means and methods of disposing of condensate from gasfurnaces, and devices that make such equipment and systems possible foroutdoor installations are needed or would be beneficial that aresufficiently reliable, inexpensive, and easy to install and service soas to be practical in a mass-production context. Needs or potential forbenefit or improvement exist for methods of manufacturing condensing gaspackage units, HVAC equipment and HVAC units having condensing furnaces,and systems and buildings having such devices. Other needs or potentialfor benefit or improvement may also be described herein or known in theHVAC or fossil fuel industries. Room for improvement exists over theprior art in these and other areas that may be apparent to a person ofordinary skill in the art having studied this document.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric top right front view of an example of an airconditioning unit packaged with a condensing gas heat exchanger forefficiently heating and cooling a space that is installed on the roof ofa building with a condensate drain line that extends from the unitthrough the roof outside of the supply and return ducts for disposal ofthe condensate, for example, within the building;

FIG. 2 is an isometric bottom right front view of an example of an airconditioning unit packaged with a condensing gas heat exchanger forefficiently heating and cooling a space that is installed on the roof ofa building with a condensate drain line that extends from the unitthrough a conduit through a separate roof penetration than the supplyand return ducts for disposal of the condensate, for instance, withinthe building;

FIG. 3 is an isometric bottom right front view of the example of an airconditioning unit of FIG. 1 that has a condensate drain line thatextends through the same enlarged roof penetration as the supply andreturn ducts for disposal of the condensate, for example, within thebuilding, and that does not use a conduit for the drain line;

FIG. 4 is an isometric bottom right front view of an example of an airconditioning unit packaged with a condensing gas heat exchanger forefficiently heating and cooling a space that is installed on the roof ofa building with a condensate drain line that extends from the unitthrough a conduit through the same (minimum size) roof penetration asthe supply and return ducts, wherein the conduit passes through the roofbetween the supply and return ducts for disposal of the condensate, forinstance, within the building;

FIG. 5 is a bottom view of the example of an air conditioning unit ofFIG. 4 that has a condensate drain line that extends through a conduitthrough the roof between the supply and return ducts for disposal of thecondensate, for example, within the building;

FIG. 6 is a cut-away left side view of the example of an airconditioning unit of FIGS. 4 and 5 taken along line A-A of FIG. 5 thathas a condensate drain line that extends through a conduit through theroof curb assembly and through the roof between the supply and returnducts;

FIG. 6 a is a detail view of part of FIG. 6 and a detail cut-away leftside view of part of the example of an air conditioning unit of FIGS.4-6 taken along section A-A of FIG. 5 that shows the penetration of thedrain line through the floor of the enclosure of the air conditioningunit and the top of the conduit in the roof curb assembly;

FIG. 7 is an isometric top right front view of an example of an airconditioning unit packaged with a condensing gas heat exchanger forefficiently heating and cooling a space that is installed on aground-level slab and that allows condensate to travel through theinducer fan and exit the enclosure of the unit with the combustiongasses, and that includes a bifurcation in the exhaust conduit from theinducer fan to separate the condensate from a portion of the combustiongasses for disposal of the condensate into the ground;

FIG. 8 is an isometric top right front view of the example of an airconditioning unit of FIG. 7 wherein the condensate is disposed of into astandpipe connected to a horizontal section of pipe with multiple holesinto the ground below the frost line;

FIG. 9 is a right side view of the example of an air conditioning unitof FIG. 8;

FIG. 10 is an isometric top left rear view of an example of an airconditioning unit packaged with a condensing gas heat exchanger forefficiently heating and cooling a space that is configured for shippingwith a conduit and drain line extending to the return duct opening forrouting of the drain line through the return duct during installation ofthe unit for disposal of the condensate (e.g., within the building);

FIG. 11 is an isometric top left front view of the example of an airconditioning unit of FIG. 2 drawn with many of the components omitted tobetter illustrate the remaining components, and illustrating thecondensing gas heat exchanger, condensate collector assembly includingthe inducer fan, burner assembly or gas manifold assembly, andcondensate drain line that extends from the collector assemblyvertically downward through the floor of the unit through the insulatedconduit, and on vertically downward, for instance, through the roof ofthe building, and that forms a loop or trap, for example, within thebuilding;

FIG. 12 is an isometric top left front view of the example of an airconditioning unit of FIGS. 1 and 3 drawn with many of the componentsomitted to better illustrate the remaining components, and illustratingthe condensing gas heat exchanger, condensate collector assemblyincluding the inducer fan, burner assembly or gas manifold assembly, andcondensate drain line that extends from the collector assemblyvertically downward through the floor of the unit without using aconduit or insulation, and on vertically downward, for instance, throughthe roof of the building, and that forms a loop or trap, for instance,within the building;

FIG. 13 is an isometric top left front view of the example of an airconditioning unit of FIGS. 4-6 a drawn with many of the componentsomitted to better illustrate the remaining components, and illustratingthe condensing gas heat exchanger, condensate collector assemblyincluding the inducer fan, burner assembly or gas manifold assembly, andcondensate drain line that extends from the collector assemblyvertically downward through the floor of the unit, and through theinsulated conduit which extends at a slope to the return and supplyducts and through the roof between the ducts;

FIG. 14 is an isometric top left front view of the example of an airconditioning unit of FIGS. 7-9 drawn with many of the components omittedto better illustrate the remaining components, and illustrating thecondensing gas heat exchanger, condensate collector assembly includingthe inducer fan, burner assembly or gas manifold assembly, and exhaustconduit or exhaust and drainage assembly for disposal of the condensateinto the ground, and further illustrating horizontal return and supplyducts which may be used when the unit is installed at ground level;

FIG. 15 is an isometric top left front view of the example of an airconditioning unit of FIG. 10 that is configured for shipping and that isdrawn with many of the components omitted to better illustrate theremaining components, and illustrating the condensing gas heatexchanger, condensate collector assembly including the inducer fan,burner assembly or gas manifold assembly, conduit, and drain lineextending to the return duct opening for routing through the return ductduring installation of the unit for disposal of the condensate, forexample, within the building;

FIG. 16 is an isometric top left front view of the example of an airconditioning unit of FIGS. 10 and 15 that is connected to verticalducts, for example, on the roof of a building, and that is drawn withmany of the components omitted to better illustrate the remainingcomponents, and illustrating the condensing gas heat exchanger,condensate collector assembly including the inducer fan, burner assemblyor gas manifold assembly, conduit extending to the return duct opening,and drain line extending through the conduit and the vertical returnduct, for instance, into the building, and then penetrating the wall ofthe return duct to form a trap and continuing downward for disposal ofthe condensate, for instance, within the building;

FIG. 17 is an isometric top left front view of the example of an airconditioning unit of FIGS. 10 and 15 that is connected to horizontalducts, for example, when the unit is installed at ground level, that isdrawn with many of the components omitted to better illustrate theremaining components, and illustrating the condensing gas heatexchanger, condensate collector assembly including the inducer fan,burner assembly or gas manifold assembly, conduit extending to thereturn duct opening, and drain line extending through the horizontalreturn duct, for instance, into the building, and then penetrating thewall of the return duct to form a trap and for disposal of thecondensate, for example, within the building;

FIG. 18 is an isometric top left rear view of the example of an airconditioning unit of FIGS. 10, 15, and 16 that is connected to verticalducts, for example, on the roof of a building, and that is drawn withmany of the components omitted to better illustrate the remainingcomponents, and illustrating, among other things, the conduit extendingfrom proximate the drain line opening penetrating the collector to thereturn duct opening and the drain line extending through the conduit andthrough the return duct, for example, into the building for disposal ofthe condensate (e.g., within the building);

FIG. 19 is an isometric bottom left rear view of the example of an airconditioning unit of FIGS. 16 and 18 that is connected to verticalducts, for example, on the roof of a building, and illustrating, amongother things, the drain line extending from the conduit through thereturn duct, and showing the trap, for instance, within the building;

FIG. 20 is an isometric top left front view of the condensate collectorassembly that may be part of the air conditioning unit of any of FIGS.1-4, 6, 7-8, and 11-18, illustrating, among other things, the inducerfan, collector, drain line opening, and fitting or elbow for connectingto the drain line, for example, for disposal of the condensate withinthe building;

FIG. 21 is an isometric top right rear view of the condensate collectorassembly of FIG. 20 that may be part of the air conditioning unit of anyof FIGS. 1-4, 6, 7-8, and 11-18, illustrating, among other things, thecollector including the drain line opening for connecting to a drainline, the exhaust hole for the inducer fan, and a drain hole below theexhaust hole, for example, for expulsion of the condensate from the unitenclosure, through the inducer fan, with the combustion gasses;

FIG. 22 is an isometric top left front view of the condensate collectorassembly of FIGS. 20 and 21 connected to the exhaust conduit or exhaustand drainage assembly of FIGS. 7-9, illustrating, among other things,the inducer fan, the collector including a plug in the drain lineopening for connecting to a drain line, the exhaust conduit or exhaustand drainage assembly for expulsion of the condensate from the unitenclosure with the combustion gasses; a bifurcation that separates thecondensate from a portion (e.g., majority) of the combustion gasses; ahigh path discharging combustion gasses into the atmosphere, and a lowpath discharging condensate and combustion gasses into a standpipe;

FIG. 23 is an isometric top right rear view of the condensate collectorassembly and exhaust conduit or exhaust and drainage assembly of FIG.22, illustrating, among other things, the collector including theexhaust hole for the inducer fan and the drain hole for expulsion of thecondensate from the unit enclosure through the inducer fan, the exhaustconduit or exhaust and drainage assembly for expulsion of the condensatefrom the unit enclosure with the combustion gasses; the bifurcation thatseparates the condensate from the portion (e.g., majority) of thecombustion gasses; the high path discharging combustion gasses into theatmosphere, and the low path discharging condensate and combustiongasses into the standpipe;

FIG. 24 is a front view of the collector that is part the condensatecollector assembly of FIGS. 20-23 and that is fitted with the plug shownin FIG. 22 in the drain line opening for connecting to a drain line,configuring the collector for expulsion of the condensate from the unitenclosure with the combustion gasses, for example, through the exhaustconduit or exhaust and drainage assembly of FIGS. 7-9, 14, 22, and 23;

FIG. 25 is a detail right side cutaway view of part of the collectortaken along line B-B in FIG. 24 that illustrates the drain line opening,fitting, and the plug shown in FIG. 22, configuring the collector forexpulsion of the condensate from the unit enclosure through the inducerfan with the combustion gasses, for example, through the exhaust conduitor exhaust and drainage assembly of FIGS. 7-9, 14, 22, and 23;

FIG. 26 is an isometric bottom left rear view of the condensing gas heatexchanger of FIGS. 11-18 illustrating, among other things, the S-tubes,U-tubes, and finned secondary heat exchanger of the embodiment shown;

FIG. 27 is an isometric top left front view of the gas manifold assemblyof the air conditioning unit packaged with a condensing gas heatexchanger of FIGS. 1-4, 6-8, and 11-18 illustrating, among other things,the multiple burners of the embodiment shown;

FIG. 28 is an isometric top right rear view of the example of an airconditioning unit of FIGS. 16, 18, and 19 that is connected to verticalducts, for example, on the roof of a building, and that is drawn withmany of the components omitted to better illustrate the remainingcomponents, and illustrating, among other things, the conduit extendingfrom the outdoor section proximate the drain line opening in thecollector to the return section, the drain line extending to and throughthe return duct, several partitions within the unit, and the trap, forinstance, within the building;

FIG. 29 is a top view of the example of an air conditioning unit ofFIGS. 16, 18, 19, and 28 that is drawn with many of the componentsomitted to better illustrate the remaining components, and illustrating,among other things, the outdoor section, return section, and heatingsection of the unit, and the drain line conduit extending from theoutdoor section proximate the drain line opening in the collector to thereturn section;

FIG. 30 is a right side view of the drain line conduit and the drainline of FIGS. 16, 18, 19, 28, and 29, illustrating, among other things,bends in the conduit and drain line, jam nuts, intake holes, an outletpassageway or cutaway opening, and an example of an apparatus forpassing a tube through a wall of a duct and for forming a trap with thetube;

FIG. 31 is a top detail cross-sectional view of part of the drain lineconduit and the drain line of FIG. 30, taken along line C-C of FIG. 30,illustrating, among other things, the jam nuts, the intake holes, theinterstitial space between the conduit and the drain line, and a seal oro-ring that seals the interstitial space from the outdoor section of theunit; and

FIG. 32 is a flow chart illustrating, among other things, a method ofreducing fuel consumption from widely used HVAC equipment bymanufacturing, obtaining, or providing condensing gas package units andadvertising installation options (e.g., that they can be installed on aroof or on the ground).

These drawings illustrate, among other things, examples of embodimentsof the invention. Other embodiments may differ.

SUMMARY OF PARTICULAR EMBODIMENTS OF THE INVENTION

This invention provides, among other things, various air conditioningunits with condensing gas heat exchangers (i.e., condensing gas packageunits) for installation outdoors that can be mounted on the roof of abuilding or on the ground, condensing gas package units configured todrain condensate through the return air duct or through the floor of theunit, condensing gas package units configured to drain condensatethrough the inducer fan, collectors for condensing heat exchangers forHVAC units, apparatuses that pass a tube (e.g., a condensate drain line)through the wall of a duct and form a trap in the tube, and methods ofreducing fuel consumption from widely used HVAC equipment bymanufacturing, obtaining, or providing condensing gas package units andadvertising that they can be installed, for example, on a roof or on theground. Various examples include air conditioning units or HVAC unitswith condensing (e.g., gas) heat exchangers, and devices, systems,methods related to such air conditioning units or HVAC units.

Various embodiments provide, for example, as an object or benefit, thatthey partially or fully address or satisfy one or more needs, potentialareas for benefit, or opportunities for improvement described herein, orknown in the art, as examples. Certain embodiments provide, for example,equipment, apparatuses, units, and methods that allow condensingfurnaces to be installed and used outdoors. In particular, variousembodiments prevent, avoid, or reduce problems that result from thefreezing of condensate from condensing furnaces that are installedoutdoors. A number of embodiments prevent, or help to prevent, frozencondensate from interfering with continued operation of the HVAC unit,from collecting, from causing a hazard or nuisance, or a combinationthereof, as examples. Certain embodiments provide, as objects orbenefits, for instance, condensing furnaces, means and methods ofdisposing of condensate from condensing furnaces, and devices that makesuch equipment and systems possible or practical. Further, particularembodiments have as an object or benefit, for example, that they aresufficiently reliable, inexpensive, and easy to install and service tobe practical for mass production, for instance, for residentialapplications. Moreover, some embodiments have as objects or benefitsthat they provide equipment or methods of manufacturing condensing gaspackage units, HVAC equipment and HVAC units having condensing furnaces,and systems and buildings having such devices.

Specific embodiments of the invention include various air conditioningunits, each packaged with a condensing gas heat exchanger, for example,for efficiently heating and cooling a space. Such a unit may include,for example, an enclosure, a return duct opening for connecting the unitto a return duct that delivers air to the unit from the space, and asupply duct opening for connecting the unit to a supply duct thatdelivers air from the unit to the space. Such a unit may also include,for instance, the condensing gas heat exchanger for heating the air, acollector connected to the condensing gas heat exchanger, and an inducerfan having an inlet connected to the collector and an outlet, and anexhaust conduit extending from the outlet of the inducer fan to outsideof the enclosure. Furthermore, in a number of embodiments, the collectorfurther has an exhaust hole for the inlet of the inducer fan, and adrain hole extending through the collector to the inlet of the inducerfan. In various embodiments, the drain hole is lower than the exhausthole for the inducer fan, the drain hole has a smaller cross-sectionalarea than the exhaust hole for the inducer fan, and condensate formed inthe condensing gas heat exchanger passes through the drain hole to theinlet of the inducer fan, through the inducer fan, and into the exhaustconduit with combustion gasses.

In some embodiments, the exhaust conduit has a bifurcation thatseparates the condensate from a majority of the combustion gasses, thebifurcation has a high path and a low path, and the high path has alarger cross sectional area than the low path. Further, in certainembodiments, the majority of the combustion gasses pass through the highpath, and a minority of the combustion gasses pass through the low pathwith the condensate. In particular embodiments, the minority of thecombustion gasses may keep the condensate from freezing when ambienttemperature conditions are below freezing. Still further, someembodiments further include, for example, a vertical standpipe. In anumber of embodiments, the low path discharges into the verticalstandpipe and the condensate is allowed to drip into the verticalstandpipe while the minority of the combustion gasses emerging from thelow path are exhausted upward between the low path and the standpipe. Insome embodiments, the standpipe extends into the ground and terminateswith at least one opening to the ground below the frost line in theground. Moreover, some embodiments further include, for example, a bedof porous alkaline material in the ground. In a number of embodiments,the condensate is directed to discharge into the bed of porous alkalinematerial in the ground to neutralize acidity of the condensate and todispose of the condensate into the ground.

Other specific embodiments of the invention include various airconditioning units packaged with a condensing gas heat exchanger thatinclude, for example, an exhaust conduit extending from the outlet ofthe inducer fan to outside of the enclosure. Such an exhaust conduit mayhave a bifurcation that separates the condensate from a majority of thecombustion gasses. In various embodiments, the bifurcation has a highpath and a low path, the high path has a larger cross sectional areathan the low path, and the majority of the combustion gasses passthrough the high path. Such embodiments may also include the enclosure,a return duct opening for connecting the unit to a return duct thatdelivers air to the unit from the space, and a supply duct opening forconnecting the unit to a supply duct that delivers air from the unit tothe space. These embodiments may also include the condensing gas heatexchanger for heating the air, a collector connected to the condensinggas heat exchanger, and the inducer fan, which may have an inletconnected to the collector as well as the outlet. In a number ofembodiments, the collector further has an exhaust hole for the inlet ofthe inducer fan, and condensate formed in the condensing gas heatexchanger passes through the inducer fan, into the exhaust conduit, andout of the enclosure.

In some embodiments, the low path has a continually downward gradient,and a minority of the combustion gasses may pass through the low pathwith the condensate to keep the condensate from freezing when ambienttemperature conditions are below freezing. Moreover, some embodimentsmay further include, for example, a vertical standpipe that may have alarger cross-sectional dimension than the low path. In a number ofembodiments, the low path discharges into the vertical standpipe and thecondensate is allowed to drip into the vertical standpipe while theminority of the combustion gasses emerging from the low path areexhausted upward between the low path and the standpipe.

Still other specific embodiments of the invention include particularmethods, for example, of reducing consumption of fossil fuels, reducingemission of greenhouse gasses, or both, for instance, from widely usedHVAC equipment. Various such methods may include, for example, in theorder indicated or in another order, (e.g., in any order) at leastcertain acts. Such acts may include, for example, manufacturing,obtaining, or providing air conditioning units that have condensing gasheat exchangers, advertising that the air conditioning units can beinstalled on a roof of a building and condensate from the condensing gasheat exchangers can be disposed of by routing a drain line through theroof of the building for disposal inside the building, and advertisingthat the air conditioning units can be installed at ground level andcondensate from the condensing gas heat exchangers can be disposed ofinto the ground.

In some embodiments, the act of manufacturing, obtaining, or providingthe air conditioning units includes manufacturing, obtaining, orproviding air conditioning units that include a condensing gas heatexchanger having at least one stage that has fins, a collector connectedto the at least one stage that has fins, and an inducer fan having aninlet connected to the collector. In a number of embodiments, thecollector has a drain line opening penetrating the collector. Moreover,in particular embodiments, the act of manufacturing, obtaining, orproviding the air conditioning units includes manufacturing, obtaining,or providing units that include a drain hole extending through thecollector to the inlet of the inducer fan. In a number of embodiments,the drain hole is higher than the drain line opening.

Further, some embodiments include, for example, an act of instructing aninstaller of the units that when they install the unit at ground leveland dispose of condensate from the condensing gas heat exchanger intothe ground, that they can leave in place, or install, a plug in thedrain line opening penetrating the collector and allow the condensate topass through the inducer fan. On the other hand, some embodimentsinclude, for example, an act of instructing an installer of the unitsthat when they install the unit on the roof of the building and disposeof condensate from the condensing gas heat exchanger in the building,that they can leave attached, or attach, the drain line to the openingpenetrating the collector, route the drain line through the roof, andallow the condensate to pass through the drain line for disposal insidethe building. Even further, some embodiments include, for example, anact of instructing an installer of the units that when they install theunit on the roof of the building and dispose of condensate from thecondensing gas heat exchanger in the building, that they can provide atrap in the drain line inside the building.

Moreover, some embodiments include, for example, an act of instructingan installer of the units that when they install the unit on the roof ofthe building and dispose of condensate from the condensing gas heatexchanger in the building, that they can install the unit on a roof curbassembly and route the drain line through a tubular conduit that passesthrough the roof curb assembly and through the roof of the building.Certain embodiments may further include, for example, an act ofinstructing an installer of the units that when they install the unit onthe roof of the building and dispose of condensate from the condensinggas heat exchanger in the building, that they can route the drain linethrough the roof of the building inside of a return duct that connectsto the unit to deliver air from within the building to the unit.

In a number of embodiments, the act of manufacturing, obtaining, orproviding the air conditioning units includes manufacturing, obtaining,or providing air conditioning units that include a return duct openingfor connecting the unit to a return duct that delivers air to the unitfrom the building. In particular embodiments, the drain line isconnected to the unit to receive the condensate and the drain lineextends to the return duct opening and is stored at the return ductopening during shipment of the unit. This configuration may be, forinstance, for routing the drain line through the return duct when theunit is installed on the roof of the building. Further, in someembodiments, the act of manufacturing, obtaining, or providing the airconditioning units may include manufacturing, obtaining, or providingair conditioning units that include a return duct opening for connectingthe unit to a return duct that delivers air to the unit from thebuilding and a tubular conduit that extends to the return duct opening.This conduit may be for routing the drain line through the return ductwhen the unit is installed on the roof of the building, for example.

Some embodiments may further include, for example, an act of instructingan installer of the units that when they install the unit at groundlevel and dispose of condensate from the condensing gas heat exchangerinto the ground, that they can install a bifurcation in an exhaustconduit extending from an outlet of an inducer fan of the unit tooutside of an enclosure for the unit. In a number of embodiments, thisact may include instructing that the bifurcation can be installed toprovide a high path and a low path, and that the low path can beinstalled to discharge into a vertical standpipe, for instance. Further,certain embodiments may include, for example, an act of instructing aninstaller of the units that when they install the unit at ground leveland dispose of condensate from the condensing gas heat exchanger intothe ground, that they can provide a low path that discharges into avertical standpipe that extends into the ground and terminates with atleast one opening to the ground below a frost line in the ground. Stillfurther, some embodiments may further include, for example, an act ofinstructing an installer of the units that when they install the unit atground level and dispose of condensate from the condensing gas heatexchanger into the ground, that they can direct the condensate todischarge into a bed of porous alkaline material in the ground toneutralize acidity of the condensate.

In addition, various other embodiments of the invention are alsodescribed herein, and other benefits of certain embodiments may beapparent to a person of ordinary skill in the art.

DETAILED DESCRIPTION OF EXAMPLES OF EMBODIMENTS

The subject matter described herein includes, as examples, variouscondensing gas package units configured for installation outdoors. Asused herein, a gas package unit is an air conditioning unit that ispackaged with a gas furnace. A number of embodiments include, forexample, with in the same enclosure, both a packaged air conditioningunit and a condensing gas heat exchanger. U.S. patent application Ser.No. 12/271,471, Publication 2010/0122806 (Halgash), illustrates anexample of a heat exchanger that may be a condensing gas heat exchanger.Condensing heat exchangers extract more heat from the products ofcombustion, which makes them more efficient than non-condensing heatexchangers. As a result, air conditioning units packaged with condensingheat exchangers are typically more efficient in a heating mode than airconditioning units packaged with non-condensing heat exchangers. In theprocess of heat extraction, however, condensation from the products ofcombustion forms in condensing heat exchangers, and this condensationmust be disposed of. Further, when ambient conditions are belowfreezing, the condensation must be disposed of without creating problemsassociated with freezing of the condensation.

Some embodiments of gas package units described herein can be mountedeither on the roof of a building or on the ground (e.g., on a groundlevel slab). Certain embodiments are suitable for installation in bothlocations. Further, some of the condensing gas package units describedherein are configured to drain condensate (e.g., liquid water condensedfrom the products of combustion) through a drain line that passesthrough the return air duct or through the floor of the unit. Such unitsmay be installed on the roof of a building, for example. Othercondensing gas package units described herein are configured to draincondensate through the inducer fan. Condensing gas package unitsdescribed herein that are configured to drain condensate through theinducer fan may be used for installation on the ground or on aground-level slab, for example.

Also described are particular collectors for condensing heat exchangers(e.g., for HVAC units such as gas package units), and apparatuses thatpass a tube (e.g., a condensate drain line) through the wall of a ductand form a trap in the tube. Also described are various methods, forinstance, of reducing fuel consumption from widely used HVAC equipmentby manufacturing, obtaining, or providing condensing gas package unitsand advertising that they can be installed on a roof or on the ground.Described are various examples of air conditioning units and HVAC unitswith condensing (e.g., gas) heat exchangers, and devices, systems,methods related to such air conditioning units and HVAC units. Moreover,other embodiments include various buildings containing such devices,companies performing one or more of the methods described herein,computer-readable storage media, computers programmed to perform amethod described herein, and computer software, as examples. Methodsdescribed herein include methods of improving HVAC units, methods ofreplacing HVAC equipment (e.g., which may provide better performance,efficiency, or both); methods of configuring HVAC units (e.g., airconditioning units), methods of providing HVAC equipment describedherein, and methods of adapting and distributing HVAC equipment (e.g.,gas package units), for instance.

As used herein, the term “HVAC unit” includes air conditioning units,heat pumps, and air conditioning units packaged with furnaces, includingcondensing furnaces. Further, “gas” furnaces and heat exchangers arementioned and described herein. The “gas” may be natural gas or propane,as examples. Other condensing furnaces or heat exchangers, however, mayburn, or may be configured to burn, other fossil fuels such as fuel oil,heating oil, gasoline, kerosene, diesel fuel, or coal, as examples.Further, some embodiments may burn a renewable fuel such as a bio fuel,wood, methane, or hydrogen, as other examples. Many aspects of equipmentconfigured for such fuels may be the same or similar to equipmentconfigured to burn natural gas or propane.

Furthermore, as used herein, if a device is said to be “configured” toperform a certain task or function, the term “configured” means that thedevice has been adapted specifically to perform that particular task orfunction, not merely that the device could be used for that particulartask or function if doing so had been contemplated. For example, as usedherein, a controller is “configured” to perform a particular task orfunction if the controller has been programmed with instructions thatwill, if executed, perform that specific task or function. A controllersimply being made to control similar equipment and being capable ofbeing programmed to perform the particular task or function is notenough, absent the software instructions to do so or other specificadaptation to accomplish the particular task or function recited.

The figures illustrate several specific embodiments of air conditioningunits, each packaged with a condensing gas heat exchanger, for example,for efficiently heating and cooling a space. In a number of embodiments,the units are configured for installation at ground level and the unitsare also configured for installation on a roof of a building. Otherembodiments, however, may be configured just for installation at groundlevel or just for installation on a roof of a building. FIGS. 1-6,11-13, 15-19, and 28-31 show air conditioning unit 1, packaged withcondensing gas heat exchanger 300 (shown in detail in FIG. 26). In FIGS.1-6, air conditioning unit 1 is shown mounted or roof 4 of a building.Just a section of roof 4 is shown. Roof 4 includes roof covering 40 androof curb flashing 41 in the embodiments shown in FIGS. 1 and 6, forexample. FIG. 10 shows air conditioning unit 3, which may be the same asair conditioning unit 1, except in a shipping configuration. Further,FIG. 15 shows part of air conditioning unit 3 in the shippingconfiguration. In contrast, FIGS. 7-9 show air conditioning unit 2 whichis shown installed on ground level (e.g., 80 shown in FIG. 9) concreteslab 5. Air conditioning units 1, 2, and 3 may be the same or similar,except as described herein, and, in some embodiments, may be bothconfigured for installation at ground level (e.g., 80 or on slab 5) andalso configured for installation on a roof (e.g., 4) of a building. Inaddition, air conditioning units 1, 2, and 3 are examples of HVAC unitsthat have condensing gas heat exchangers and collectors, as describedherein.

In the embodiments illustrated, air conditioning units 1 and 3 eachinclude single outer enclosure 10, and air conditioning unit 2 includessingle outer enclosure 20. In some embodiments, enclosures 10 and 20 maybe similar or identical. As shown in FIG. 29, each unit 1 includes, forexample, within single enclosure 10, outdoor section 291, return section292, and heating section 293. When unit 1 is in operation, outdoorsection 291 contains outdoor air and is normally at the ambienttemperature except for temperature differences resulting from heattransfer from the other sections. Return section 292, on the other hand,contains return air from the building and is normally at the temperaturewithin the building, potentially differing therefrom only slightly as aresult of any heat transfer in the ductwork or unit. Further, heatingsection 293 contains heat exchanger 300, which, when in operation, heatsthe air in return section 293 substantially above that of return section292. An indoor air fan or blower (not shown) blows air from returnsection 292 into heating section 293. As a result, the static pressurewithin heating section 293 is normally higher than the static pressurewithin return section 292 when unit 1 is in operation (when the indoorair fan or blower is operating).

Unit 1 also includes supply duct opening 297 for connecting the unit toa supply duct that delivers air from the unit (e.g., from heatingsection 293) to the space (e.g., within the building). As used herein,unless stated or apparent otherwise, if two components are said to be“connected” (and variations thereof such as “connecting”) thosecomponents may be directly connected or may be indirectly connected viaone or more other components (e.g., other than those parts shown ordescribed herein) that may perform no other significant function beyondthe connection described. For example, a duct is said to be “connected”to a unit even if there is an extension or flexible coupling between theduct and the unit. Similarly, a drain line is said to be connected to acollector or to an opening therein even if there is a fitting (e.g.,102) between the drain line and the collector.

In the embodiment illustrated, supply duct opening 297 is in heatingsection 293. In addition, in the embodiment shown, return section 292contains return duct opening 296 for connecting the unit to a returnduct that delivers air to the unit from the space (e.g., within thebuilding). FIGS. 2-5 show (e.g., a section of) vertical return duct 61and FIGS. 2-6 show (e.g., a section of) vertical supply duct 62, whichare connected to return duct opening 296 and supply duct opening 297respectively. In addition, FIGS. 16, 18, 19, and 28 show (e.g., asection of) vertical return duct 63 and FIGS. 16, 18, and 19 show (e.g.,a section of) vertical supply duct 62, which, in other embodiments, areconnected to return duct opening 296 and supply duct opening 297respectively. Omitted in FIG. 29, but shown in FIGS. 11-18, heatingsection 293 also contains condensing (e.g., gas) heat exchanger 300.

As illustrated in FIGS. 7-9, 14, and 17, in some embodiments, and insome applications, air conditioning units or gas package units (e.g., 1or 2, for instance, packaged with a condensing heat exchanger 300, forexample) may be connected to horizontal ducts (e.g., return duct 71 andsupply duct 72 shown in FIGS. 14 and 17) rather than to vertical ducts(e.g., 61 and 62 or 62 and 63 shown in FIGS. 2-6, 11-13, 16, 19, and28). As shown in FIGS. 10, 14, and 17, in particular embodiments, theair conditioning units are fitted with return duct opening 296 andsupply duct opening 297 for vertical ducts (e.g., 61 and 62 or 62 and63) and also with return duct opening 171 and supply duct opening 172for horizontal ducts (e.g., 71 and 72). When not connected to a verticalduct, return duct opening 296 and supply duct opening 297 for verticalducts may be covered with opening covers 75 and 74, respectively, (e.g.,as shown in FIGS. 14, 15, and 17). Similarly, when not connected to ahorizontal duct, return duct opening 171 and supply duct opening 172 forhorizontal ducts may be covered with opening covers such as openingcover 1723 show in FIG. 10 covering supply duct opening 172. Openingcovers may be sheet metal, for example, and may be secured withfasteners such as sheet metal screws, for instance.

In the embodiment illustrated, outdoor section 291 further includesburners 431, 432, 433, 434, and 435, of burner assembly or gas manifoldassembly 400 shown in FIGS. 6 and 11-18, and in detail in FIG. 27. Inthe embodiment shown, burners 431, 432, 433, 434, and 435, of gasmanifold assembly 400 fire into condensing gas heat exchanger 300.Although five burners are shown, various embodiments include one or moreburners firing into the condensing gas heat exchanger. As used herein,“one or more” means at least one. Different embodiments may have 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 burners firing into thecondensing gas heat exchanger, as examples. As illustrated in FIG. 27,in the embodiment illustrated, burner assembly or gas manifold assembly400 further includes gas valve 420, gas manifold pipe 410, and gasmanifold pipe bracket 440.

In the embodiment depicted, outdoor section 291 further includescollector pan or collector 101 connected to condensing gas heatexchanger 300, and inducer fan 104 having inlet 1016 connected tocollector 101 labeled by reference number in FIGS. 20-24. In addition,collector 101 and inducer fan 104 are part of collector assembly 100(e.g., configured for internal drainage) and 200 (e.g., configured forexternal drainage through inducer fan 104) shown in FIGS. 1-4, 6, 7-8,11-18, and 20-23. In a number of embodiments, inducer fan 104, whenoperating, draws air past the one or more burners (i.e., burners 431,432, 433, 434, and 435, of gas manifold assembly 400, in the embodimentshown) and draws combustion gasses through the condensing gas heatexchanger (e.g., 300) and collector (e.g., 101) and exhausts thecombustion gasses through an outlet (e.g., 105 shown in FIGS. 20-23) ofthe inducer fan (e.g., 104) to outside of the enclosure (e.g., 10 or20). Relative to the combustion gasses, collector 101 is downstream ofheat exchanger 300 and collector 101 collects the substantially cooledcombustion gasses and condensate emerging from heat exchanger 300.

Condensing heat exchanger 300 is shown in detail in FIG. 26, althoughother embodiments may differ. In the embodiment illustrated, heatexchanger 300 includes five primary S tubes 341, 342, 343, 344, and 345that burners 431, 432, 433, 434, and 435 (shown in FIG. 27) fire into.At lower pan 322, products of combustion or combustion gasses fromprimary S tubes 341, 342, 343, 344, and 345 flow into intermediateU-tubes 331, 332, 333, 334, and 335. Further, at upper pan 321, productsof combustion from intermediate U-tubes 331, 332, 333, 334, and 335 flowinto finned secondary heat exchanger 312. In the embodiment illustrated,both pans 321 and 322 attach to header plate 311. Other embodiments mayuse separate or multiple header plates, as another example. Further,although the embodiment of heat exchanger 300 that is illustratedincludes five each of primary S tubes 341, 342, 343, 344, and 345 andintermediate U-tubes 331, 332, 333, 334, and 335, other embodiments mayhave one or more primary S tubes and one or more intermediate U-tubes asother examples. For instance, other embodiments may have 1, 2, 3, 4, 6,7, 8, 9, 10, 11, 12, 13, 14, or 15 primary S tubes and 1, 2, 3, 4, 6, 7,8, 9, 10, 11, 12, 13, 14, or 15 intermediate U-tubes as other examples.

Further, in some embodiments, the heat exchanger tubes may have adifferent shape. In different embodiments there may be first a U shapeand then an S shape, or there may be a W shape, as examples. Further, insome embodiments, there may be multiple passes or stages that includefins. Moreover, in the embodiment illustrated, the primary S tubes 341,342, 343, 344, and 345 are larger in diameter than intermediate U-tubes331, 332, 333, 334, and 335. Finned secondary heat exchanger 312 mayhave tubes that are smaller in diameter but more numerous than theintermediate tubes (e.g., U-tubes 331, 332, 333, 334, and 335). In theembodiment illustrated, condensation of some of the products ofcombustion (e.g., steam or water vapor) may take place in finnedsecondary heat exchanger 312. Finned secondary heat exchanger 312 mayterminate at header plate 313, and condensate formed therein may flow toheader plate 313. As described in more detail below, in the embodimentillustrated, flange 1015 (shown, for example, in FIGS. 21 and 23) ofcollector 101 may attach to header plate 313 where products ofcombustion, including combustion gasses and condensate, may becollected. Header plate 313, finned secondary heat exchanger 312, heatexchanger 300, or a combination thereof, may be made of metal, such asaluminized steel, stainless steel, austenitic stainless steel, orsuperferritic (super ferritic) stainless steel, for example, AL 29-4c orUNS S44735.

Further, in the embodiment illustrated, outdoor section 291 (e.g., shownin FIG. 29) further includes, for example, drain line opening 1012(shown, for example, in FIGS. 21-23, and in detail in FIG. 25)penetrating collector 101. In the embodiment illustrated, drain lineopening 1012 is threaded and threaded fitting or elbow 102 is shown(e.g., in FIGS. 20, 22, 24, and 25) screwed into drain line opening1012. Except where a different meaning is apparent, as used herein, thephrase “drain line opening penetrating the collector” may include afitting, such as fitting 102, connected to the collector, if such afitting is used in that embodiment. In the embodiment shown, outdoorsection 291, and collector 101 further include drain hole 1011 (shown,for example, in FIGS. 21, 23, and 24) extending through collector 101 tothe inlet (e.g., 1016) of inducer fan 104. Further still, in theembodiment illustrated, when air conditioning unit 1 or 2 is installedand leveled properly in accordance with the manufacturer's installationinstructions, drain hole 1011 is higher than drain line opening 1012.

In various embodiments, the drain line opening (e.g., 1012) penetratingthe collector (e.g., 101), the fitting (e.g., 102) connected thereto, orboth, are in the outdoor section (e.g., 291). In other embodiments, thedrain line opening (e.g., performing a function similar to drain lineopening 1012) is located in the heating section (e.g., 293) and may beconnected to the heat exchanger (e.g., 300). Such a configuration avoidsrisk of condensate freezing at the drain line opening or in the drainline within the heating section due to the heat from the heat exchanger(e.g., 300). Locating the drain line opening (e.g., 1012) penetratingthe collector (e.g., 101), the fitting (e.g., 102) connected thereto, orboth, in the outdoor section (e.g., 291), however, may protect thefitting (e.g., 102), drain line, or both, from direct heat from heatexchanger 300, may provide easier access to the drain line opening(e.g., 1012), the fitting (e.g., 102) connected thereto, the connectionto the drain line (e.g., 160, 161, 162, 163, 164, or 165) or acombination thereof, or may provide a combination of such benefits.Further, in a number of embodiments, the outdoor section (e.g., 291),near burner assembly or gas manifold assembly 400, may not get very cold(e.g., below freezing), at least when the unit is operating, due to heatfrom burner assembly 300 or gas manifold assembly 400, from collectorassembly 100 (including inducer fan 104 and exhaust conduit 106 or 506),through partition 111 or 131 (shown, for example, in FIGS. 11-18, 28,and 29), or a combination thereof.

In a number of embodiments, an example of which is illustrated in FIG.29, the drain line opening (e.g., 1012) penetrating the collector (e.g.,101) is in the outdoor section (e.g., 291) and a tubular conduit (e.g.,135) extends from the outdoor section (e.g., 291) to the return ductopening (e.g., 296 or 171). As used herein, a conduit or drain line issaid to extend to the return duct opening (e.g., 296 or 171) if theconduit or drain line extends into the return section (e.g., 292) and iswithin reach through the return duct opening (e.g., 296 or 171), forinstance, before the unit is installed or connected to the ductwork. Inthe embodiment shown, tubular conduit 135 extends from outdoor section291, where conduit 135 is attached to partition 131 with jam nut 137shown in FIGS. 15, 30, and 31, through partition 131 shown in FIGS.15-18, 28, and 29, through jam nut 138 shown in FIGS. 18, 28, 30, and31, and into heating section 293. Further, in particular embodiments(e.g., as shown in FIG. 29), the tubular conduit (e.g., 135) passesthrough the heating section (e.g., 293), then through the outdoorsection (e.g., 291), and then to the return section (e.g., 292). In theembodiments shown, for example, in FIGS. 15-18 and 28-31, condensatedrain line 163 or 164 attaches to drain line opening 1012 penetratingcollector 101 in outdoor section 291.

Further, in the embodiments illustrated, after the condensate drain line(e.g., 163 or 164) attaches to drain line opening 1012 (e.g., viafitting 102) at collector 101, the condensate drain line passes intoheating section 293 through jam nut 137 shown in FIGS. 15, 30, and 31and jam nut 138 shown in FIGS. 18, 30, and 31. In this embodiment, jamnuts 137 and 138 attach conduit 135 to partition 131 shown, for example,in FIGS. 15-18, 28, and 29. Even further, in the embodiments shown,condensate drain line 163 or 164 passes through heating section 293,then through grommet 141 (e.g., shown in FIGS. 15-18, 28, and 30)through partition 133 (shown in FIGS. 28 and 29) and into outdoorsection 291, and then through grommet 142 (e.g., shown in FIGS. 15-18,28, and 30) and partition 134 (shown, for example, in FIGS. 28 and 29)and into return section 292. In the embodiment shown, conduit 135attaches to floor 132 with jam nuts 139 (e.g., shown in FIGS. 15, 17,18, 28, and 30) and 140 (e.g., shown in FIGS. 19 and 30). In thisembodiment, condensate drain line 163 or 164 can pass through jam nuts139 and 140 into return air duct 63 as shown in FIGS. 16, 18, 19, 28,and 30, or can exit conduit 135 at cutaway opening 1355 as shown inFIGS. 15 and 17. Grommets 141 and 142 may be similar to grommet 1636shown in more detail in FIG. 6 a, for example, and jam nuts 137, 138,139, and 140 may be similar to jam nuts 1639 and 1640. Other embodimentsmay route the condensate drain line differently, but in the airconditioning unit illustrated, the routing described and shown avoidscomponents such as the air conditioning evaporator coil (e.g., 610 shownin FIG. 6), and also provides access to where the condensate drain lineattaches to the collector and to the condensate drain line at returnduct opening 296 or 171.

In the embodiments illustrated, inducer fan 104, when operating, drawsair past burners 431, 432, 433, 434, and 435 (e.g., shown in FIG. 27),of burner assembly or gas manifold assembly 400 (e.g., shown in FIGS.1-4, 6, 7-8, 11-18, and 27) and draws combustion gasses throughcondensing gas heat exchanger 300 (e.g., shown in FIGS. 11-18 and 26)and through collector 101 (e.g., shown in FIGS. 20-25 and 28). Asdescribed herein, different embodiments may have one or more burners. Inthe embodiment illustrated in FIGS. 7-9, 14, and 22-25), inducer fan 104further exhausts the combustion gasses through outlet 105 of inducer fan104 to outside of enclosure 20 of HVAC unit 2.

Collector 101 is an example of a collector for a condensing gas heatexchanger (e.g., 300) for an HVAC unit (e.g., air conditioning unit 1,2, or 3). As shown in FIG. 21, collector 101 includes exhaust hole 1013for inducer fan 104, in addition to drain line opening 1012 penetratingcollector 101, and drain hole 1011 extending through collector 101 toinlet 1016 of inducer fan 104. In the embodiment shown, exhaust hole1013 for inducer fan 104 is connected to inlet 1016 of inducer fan 104.Further, in the embodiment depicted, when HVAC unit 2 is installed foroperation, drain line opening 1012 penetrating collector 101 is lowerthan exhaust hole 1013 for the inducer fan. Moreover, when HVAC unit 2is installed for operation, drain hole 1011 is higher than drain lineopening 1012, and drain hole 1011 is lower than exhaust hole 1013 forinducer fan 104.

In the embodiment shown, for example, in FIGS. 21 and 23, exhaust hole1013 for inducer fan 104 is round. In addition, in this particularembodiment, drain line opening 1012 penetrating collector 101 isthreaded, as shown, for instance, in FIG. 25, and drain hole 1011 has asmaller cross-sectional area than exhaust hole 1013 for inducer fan 104.In different embodiments, some or a combination of these relationshipsmay exist. Further, in the embodiment illustrated, collector 101includes flange 1015 (e.g., identified in FIGS. 21 and 23) having aperimeter with multiple holes 1017 spaced around the perimeter forconnection of collector 101 to condensing gas heat exchanger 300 of theHVAC unit (e.g., 1, 2, or 3), for instance, at header plate 313 shown inFIG. 26, for example, with multiple fasteners. Such fasteners, and otherfasteners described herein, may be screws, bolts, clips, or rivets, asexamples. In a number of embodiments, fasteners (e.g., larger fasteners,for instance, bolts or screws) may also secure inducer fan 104 tocollector 101, for example, as shown. Collector 101 may be plastic, butmay attach to and seal against heat exchanger 300 (e.g., to header plate313), that may be metal. A gasket, o-ring, seal, or sealing adhesive maybe used to form a seal, in some embodiments. The housing of inducer fan104 may also be plastic.

Various embodiments include a condensate drain line connected to thedrain line opening (e.g., 1012, for instance, via fitting 102)penetrating the collector (e.g., 101). Examples include drain line 162shown in FIGS. 4, 5, 6, and 6 a; 161 shown in FIGS. 2 and 11; 163 shownin FIGS. 10 and 15; 160 shown in FIGS. 1, 3, and 12; 164 shown in FIGS.16, 18, 19, and 28-31; and 165 shown in FIG. 17. For instance, FIGS. 10and 15 show condensate drain line 163 that extends to return ductopening 296 for routing through return duct 63 (e.g., shown in FIGS. 16,18, 19, and 28) for disposal of the condensate, for instance, within thebuilding. Moreover, a number of embodiments further include a tubularconduit through which the condensate drain line passes. Examples includeconduit 1612 shown in FIGS. 2 and 11; conduit 1622 shown in FIGS. 4, 6,6 a, and 13; and conduit 135 shown in FIGS. 10, 15-18, and 28. In someembodiments, conduit may be installed first and used to guide thecondensate drain line, for example, through the unit or through a roofor a roof curb assembly (or both). In various embodiments, the conduitmay be rigid and may be straight or include bends (e.g., as shown). Inother embodiments, however, flexible, soft, corrugated, or spiralconduit may be used, as other examples.

In the embodiment illustrated in FIGS. 10, 15-18, and 28 of tubularconduit 135, condensate drain line 163, 164, or 165 passes throughtubular conduit 135 between drain line opening 1012 penetratingcollector 101 and return duct opening 296 or 171. As shown in FIG. 29,in the embodiment illustrated, condensate drain line 164 and conduit 135pass through heating section 293. In this embodiment, tubular conduit135 protects condensate drain line 164 from direct heat from condensinggas heat exchanger 300 where condensate drain line 164 passes throughheating section 293. Tubular conduit 135 may be made of a material, suchas a metal, that can withstand a high temperature. Examples includealuminum, steel, galvanized steel, aluminized steel, stainless steel,and copper. Drain line 164, on the other hand, or other condensate drainlines described herein, may be flexible, and may be made of a polymer orplastic, for example, such as polyethylene, vinyl, or polyvinylchloride(PVC), as examples. In other embodiments, however, the conduit may beplastic, such as a thermoset plastic or a thermal plastic.

As used herein, an object is considered to be protected from “directheat” from a particular source of heat if there is a layer of solidmaterial between the object and the source of heat. Most radiant heatfrom the heat source (e.g., heat exchanger 300) may be prevented fromreaching the object (e.g., drain line 164) by the layer of solidmaterial (e.g., conduit 135). But some heat from the heat source mayreach the object despite the layer of solid material. For example,convective heat from the heat source (e.g., heat exchanger 300) mayreach the object (e.g., drain line 164), or the layer of solid material(e.g., conduit 135) may absorb radiant heat from the heat source (e.g.,heat exchanger 300) and then may re-radiate heat, or heat may betransferred by convection, or conduction to the object (e.g., drain line164), as examples. Multiple modes of heat transfer may occursimultaneously.

Furthermore, in the embodiment shown, condensate drain line 164 passesthrough outdoor section 291 and tubular conduit 135 protects condensatedrain line 164 from freezing where condensate drain line 164 passesthrough outdoor section 291. As shown in FIG. 31, in the embodimentillustrated, annular interstitial space 310 is formed between or definedby condensate drain line 164 and tubular conduit 135. Further, in theembodiment shown, intake holes 1351, 1352, 1353, and 1354 form inletpassageways from heating section 293 to interstitial space 310. Inaddition, in this embodiment, cutaway opening 1355, shown in FIGS. 10,18, and 30, for instance, is an outlet passageway from interstitialspace 310 to return section 292. In the embodiment shown, when the unit(e.g., unit 1) is operating, air flows from heating section 293, throughinlet passageways 1351, 1352, 1353, and 1354, through interstitial space310 along condensate drain line 164, and out outlet passageway 1355 toreturn section 292. This may keep condensate drain line 164 fromfreezing where condensate drain line 164 passes through outdoor section291, or may warm drain line 164 at that location. Interstitial space 310is blocked, in this embodiment, at partition 131 (e.g., at jam nuts 137and 138) by seal or o-ring 136 shown in FIG. 31 to prevent (e.g., cold)outdoor air from outdoor section 291 from being drawn into interstitialspace 310 and therethrough into return section 292 through opening 1355,for example. In some embodiments, similar o-rings may be used at ends ofconduits or where jam nuts are used, but in a number of embodiments,similar o-rings may not be needed at other ends of conduits or whereother jam nuts are used.

In the embodiment illustrated, return duct opening 296 is open to returnsection 292. A blower or indoor air fan (not shown) located withinenclosure 10 of unit 1 or 3 (e.g., above heat exchanger 300) blowsindoor air from return section 292 into heating section 293. As aresult, the static pressure within heating section 293 is higher thanthe static pressure within return section 292. This difference in staticpressure causes the airflow from heating section 293, through inletpassageways 1351, 1352, 1353, and 1354, through interstitial space 310,along condensate drain line 164, and out outlet passageway 1355, forexample, to return section 292. The flow through interstitial space 310,however, is small in comparison with the flow provided by the indoor airfan, and power losses resulting from the flow through interstitial space310 are negligible.

Several of the figures illustrate embodiments in which the drain linepasses through the return air duct (e.g., 63 or 71). Other embodiments,however, may pass the drain line through the supply duct (e.g., 62). Adrain line inside the supply duct will typically also avoid freezingwhen outdoor air temperatures fall below freezing. In some embodiments,however, drain line routing to the supply duct opening (e.g., 297) maybe more problematic, or sufficient pressure differential may not existto provide flow through the interstitial space (e.g., 310) to avoidfreezing where the drain line passes through the outdoor section (e.g.,291) of the unit. In some embodiments, for example, the drain line maybe routed through the supply duct (e.g., 62), but the conduit for thedrain line may terminate in the return section (e.g., 292) or an outletpassageway (e.g., analogous to 1355) may be provided from theinterstitial space (e.g., 310) to the return section (e.g., 292), asother examples. In certain embodiments, as another example, the drainline may be routed through the supply duct (e.g., 62), and the conduitfor the drain line may terminate in the heating section (e.g., 293) ornear the supply duct opening (e.g., 297) or an outlet passageway (e.g.,analogous to 1355) may be provided from the interstitial space (e.g.,310) to the heating section (e.g., 293) or to the supply duct opening(e.g., 297), as still other examples.

In the embodiment shown, inlet passageways 1351, 1352, 1353, and 1354,and outlet passageway 1355 are holes in conduit 135. In otherembodiments, however inlet passageways, outlet passageways, or both, maybe longer or may include tubing themselves, for instance, connected tothe conduit, for example, with a tee. For example, in some embodiments,condensate drain line conduit may pass from the outdoor section (e.g.,291) directly to the return section (e.g., 292) without passing throughthe heating section. In some such embodiments, however, one or moretubes may extend from the heating section (e.g., 293) to theinterstitial space between the drain line and the drain line conduit.These one or more tubes may constitute the inlet passageway(s) describedherein, and may provide a pathway for heated air from the heatingsection to travel through the interstitial space to the return section,to keep the drain line from freezing or to thaw the drain line if it isalready frozen. Further, as previously mentioned, in some embodiments,condensate drain line conduit might not go through the return section(e.g., 292), but one or more tubes may extend from the interstitialspace (e.g., 310) between the drain line and the drain line conduit tothe return section (e.g., 292). These one or more tubes may constitutethe outlet passageway(s) described herein, and may provide a pathway forheated air from the heating section to travel through the interstitialspace to the return section, to keep the drain line from freezing or tothaw the drain line if it is already frozen. For example, such a drainline may extend outside of the return and supply ducts, or may passthrough the supply duct, as examples.

For example, in some embodiments, condensate drain line conduit may passthrough the roof outside of either duct and yet may be heated (e.g.,through the interstitial space) with warm air from the heating section(e.g., 293) that is delivered to the return section (e.g., 292). In somesuch embodiments, one or more inlet tubes may extend from the heatingsection (e.g., 293) to the interstitial space between the drain line andthe drain line conduit. These one or more inlet tubes may constitute theinlet passageway(s) described herein, and may provide a pathway forheated air from the heating section to travel through the interstitialspace to keep the drain line from freezing or to thaw the drain line ifit is already frozen. Further, in some such embodiments, one or moreoutlet tubes may extend from interstitial space between the drain lineand the drain line conduit to the return section (e.g., 292) or to thereturn air duct (e.g., 61 or 63). These one or more outlet tubes mayconstitute the outlet passageway(s) described herein, and may provide apathway for the heated air from the heating section to travel throughthe interstitial space to the return section or return duct. Forexample, such a drain line and drain line conduit may extend through theroof as shown in FIG. 2, 4, 6, 11, or 13, as examples.

Air conditioning unit 3, shown in FIGS. 10 and 15, is shipped (e.g.,from the manufacturer) with condensate drain line 163 installed inconduit 135 and coiled at return duct openings 296 and 171. In otherembodiments, the air conditioning unit may be shipped (e.g., from themanufacturer) with the conduit in place and the installer may pass thecondensate drain line through the conduit, as another example. Airconditioning unit 3, shown in FIGS. 10 and 15, is an example of anembodiment having a tubular conduit (e.g., 135) that extends fromproximate a drain line opening (e.g., 1012) penetrating the collector(e.g., 101) to the return duct opening for routing the condensate drainline (e.g., 135) from the drain line opening (e.g., 1012) penetratingthe collector (e.g., 101) to the return duct opening (e.g., 296 or 171)and through the return duct (e.g., 63 or 71 and 73 shown in FIGS. 16-18)for disposal of the condensate, for example, within the building. Inthis context, as used herein, “proximate” means within 18 inches, withinthe same section (e.g., outdoor section), and with no partitions orcomponents blocking routing of the drain line therebetween. In variousembodiments, the unit has (e.g., at least one of) a condensate drainline connected to the drain line opening (e.g., 160, 161, 162, 163, 164,or 165) or a tubular conduit (e.g., 135, 1612, or 1622) for passing sucha condensate drain line. Some embodiments may include (e.g., supplied bythe manufacturer, as shown in FIGS. 10 and 15) both the drain line andthe conduit.

Various embodiments include a floor, for instance, of enclosure 10 or 20or a unit base pan, for example, floor 112 shown in FIGS. 6, 6 a, and11-14; or floor 132 shown in FIGS. 15-19, 28, and 29. Certainembodiments are air conditioning units packaged with condensing gas heatexchangers (e.g., 300) that include, for example, a drain line hole inthe floor of the enclosure (e.g., 10 or 20) for the unit for passing adrain line (e.g., 160, 161, or 162). Drain line hole 1635 in floor 112in FIGS. 6, 6 a, and 11-13 is an example. Floor 112 may be sheet metal,for example, and hole 1635 may be stamped or drilled therein, forinstance. Hole 1635 may be round and may be lined with grommet 1636shown in FIG. 6 a, for example. Grommet 1636 may be plastic orelastomeric, and may protect the condensate drain line (e.g., 160, 161,or 162) from damage resulting from edges of hole 1635, may reduce airleakage between hole 1635 and the condensate drain line (e.g., 160, 161,or 162), may help to hold the condensate drain line in place, or acombination thereof, as examples.

In various embodiments, such as the embodiment illustrated, drain linehole 1635 is located substantially below the drain line opening (e.g.,1012). This location is for passage of drain line 160, 161, or 162 fromdrain line opening 1012 through drain line hole 1635, for disposal ofthe condensate (e.g., within the building). In this context,“substantially below” means within 30 degrees from vertical belowopening 1012 or fitting 102. In certain embodiments, drain line hole1635 is located below drain line opening 1012 or fitting 102 to within60, 45, 20, 15, 10, 7.5, 5, 4, 3, 2, 1, or 0.5 degrees from vertical, asother examples. In the embodiments illustrated, floor 112 is forembodiments that have a vertical, nearly vertical, substantiallyvertical, or straight-down condensate drain line (e.g., 160, 161, or162, for instance, through outdoor section 291) and floor 132 is forembodiments that have an internal drain line (e.g., 163, 164, or 165) ora drain line that passes through the return duct (e.g., 63 or 71). Insome embodiments, however, the floor may be the same for both drain lineconfigurations. In some embodiments, in fact, the floor and unit may beconfigured (e.g., with hole 1635) for a straight-down condensate drainline (e.g., 160, 161, or 162) and the floor and unit may also beconfigured for an internal drain line (e.g., 163, 164, or 165) or adrain line that passes through the return duct (e.g., 63). In someembodiments, for example, hole 1635 may be partially stamped so that itcan easily be punched out in the field by an installer, or may beprovided with a plug that the unit installer can install or leave inplace if hole 1635 is not used and that the installer can remove or notuse if hole 1635 is used for the condensate drain line (e.g., 160, 161,or 162).

In the embodiment illustrated in FIGS. 1-6 and 11-13, condensate drainline 160, 161, or 162 is connected to drain line opening 1012 (i.e., viafitting 102) penetrating collector 101. In these embodiments, condensatedrain line 160, 161, or 162 extends vertically downward from drain lineopening 1012 (or from fitting 102) through floor 112. As used herein,this means that opening 1012 is above floor 112 and that condensatedrain line 160, 161, or 162 is vertical, to within 10 degrees, at leastfrom fitting 102 to floor 112. In other embodiments, the condensatedrain line extends substantially vertically downward from the drain lineopening through the floor. As used herein, this (substantially vertical)means that the drain line opening is above the floor and that thecondensate drain line is vertical, to within 20 degrees, at least fromopening 1012 or fitting 102 to floor 112. In still other embodiments,the condensate drain line extends vertically downward, to within 30, 25,15, 10, 5, 2.5, or 1 degrees, from the drain line opening or fittingthrough the floor.

In particular embodiments, when the unit (e.g., 1) is installed on theroof (e.g., 4), the tubular conduit (e.g., conduit 1612 shown in FIGS. 2and 11 or conduit 1622 shown in FIGS. 4, 6, 6 a, and 13) issubstantially vertical at the floor (e.g., 112) of the enclosure (e.g.,10) of the unit (e.g., 1) and the drain line hole (e.g., 1635) in thefloor (e.g., 112) is directly below the drain line opening (e.g., 1012or fitting 102) in the collector (e.g., 101). As used herein, in thiscontext, “substantially vertical” means vertical to within 20 degrees,and “directly below” means vertically below to within 5 degrees. In someembodiments, the tubular conduit is vertical at the floor of theenclosure to within 30, 15, 10, 5, 3, 2, or 1 degrees. And in someembodiments, the drain line hole (e.g., 1635) in the floor is below thedrain line opening (e.g., 1012 or fitting 102) in the collector (e.g.,101) to within 30, 20, 15, 10, 3, 2, or 1 degrees from vertical, asother examples. Furthermore, in the embodiments shown in FIGS. 2, 4, and11, when unit 1 is installed on roof 4, tubular conduit 1612 or 1622 issubstantially vertical (i.e., vertical to within 20 degrees) from floor112 of enclosure 10 of the unit through roof 4 of the building.

On the other hand, in the embodiments shown in FIGS. 4, 6, and 13,tubular conduit 1622 extends from drain line hole 1635 in floor 112 at aslope to return duct 61 and supply duct 62, and through roof 4 of thebuilding between return duct 61 and supply duct 62 through penetration42. Further, the embodiment illustrated (e.g., in FIG. 6) includes roofcurb assembly 45 for supporting unit 1 on roof 4 and containing returnduct 61 and supply duct 62. In the embodiment shown, roof curb assembly45 includes tubular conduit 1622 therethrough for passage of condensatedrain line 162, for example, for disposal of the condensate, forinstance, within the building. As illustrated, tubular conduit 1622extends from floor 112, through roof curb assembly 45, and through roof4 of the building, through penetration 42. In this embodiment, thesmaller penetration 42 is used without needing additional penetration 44(shown in FIG. 2, for example) for the drain line.

Moreover, in the embodiment shown, tubular conduit 1622 extends fromvertically below drain line opening 1012 (e.g., at floor 112), bendsless than 90 degrees, and then continues at a slope through roof curbassembly 45 to supply duct 62 (shown in FIGS. 6 and 13) and return duct61, and through roof 4 of the building between return duct 61 and supplyduct 62. As used herein, a conduit (e.g., 1622) extends “to” a duct(e.g., 61 or 62) if the conduit comes to within twelve (12) inches fromthe duct. Further, as used herein, if a conduit passes between twoducts, and the ducts are closer together than their majorcross-sectional dimension, then the conduit is said to extend “to” thetwo ducts. In some embodiments, such as illustrated in FIGS. 5, 6, and13, the conduit (e.g., 1622) extends to within 12, 5, 4, 3, 2, or 1inches from one or both ducts (e.g., 61 and 62), as further examples.

As shown in FIGS. 6 and 13, in the embodiment shown, there is a secondbend of less than 90 degrees in conduit 1622 at ducts 61 and 62 from thesloped section to a further substantially vertical section of theconduit and drain line. The slope (e.g., between the two bends) may be,for example, (e.g., when the unit, roof curb assembly, and conduit areproperly installed), more than zero degrees but less than 90 degreesfrom horizontal, more than zero degrees but less than 45 degrees fromhorizontal, more than zero degrees but less than 30 degrees fromhorizontal, more than five degrees but less than 30 degrees fromhorizontal, or more than five degrees but less than 20 degrees fromhorizontal, as examples of ranges. The embodiment shown (e.g., in FIGS.6, 6 a, and 13) includes insulation 1623 (e.g., foam) around conduit1622. Other embodiments, on the other hand, may omit insulation (e.g.,as shown in FIGS. 3, 12, 15-19, and 28-30) or may have insulationdirectly on the condensate drain line rather than surrounding a conduit(e.g., insulation 56 on low path 57, which may be a drain line or hose,as shown in FIGS. 22 and 23), as other examples.

Further, as shown in FIGS. 4, 6, and 13, conduit 1622 is supported fromducts 61 and 62 by mounting bracket 1624. As shown in FIG. 6 a, conduit1622, in the embodiment illustrated, is also supported from roof curbtop front close-out pan 455 of roof curb assembly 45 by jam nuts 1639and 1640. Moreover, FIG. 6 a also shows roof curb front long side panel451 and roof curb front panel wooden nail rail 453, and FIG. 5 showsroof curb rear long side panel 452 and roof curb long duct support 457that supports ducts 61 and 62 from roof 4, which are components of roofcurb assembly 45, in the embodiment shown. In addition, FIG. 6 showsroof curb front long side panel 451, roof curb front panel wooden nailrail 453, roof curb rear long side panel 452, roof curb short ductsupport 458, and roof curb rear panel wooden nail rail 454, which arealso components of roof curb assembly 45, in the embodiment illustrated.FIG. 6 also shows roof curb top front close-out pan 455, roof curb topcenter close-out pan 456, and roof curb long duct support 457. Otherembodiments may differ.

Further, FIGS. 11 and 12 illustrate embodiments where condensate drainline 160 or 161 extends vertically downward from drain line opening 1012(i.e., from fitting 102) penetrating collector 101 through floor 112 andon vertically downward (i.e., vertical to within 10 degrees) throughroof 4 (shown in FIGS. 1 and 2) of the building for disposal of thecondensate (e.g., within the building). As shown in FIG. 2, in some suchembodiments, the drain line passes through the roof through a separatepenetration (e.g., penetration or round hole 44) than the penetration(e.g., 42) for the return and supply air ducts 61 and 62. As illustratedin FIG. 3, however, in other embodiments, roof penetration 43 may beused that is larger and extends to the drain line (e.g., 160) so that asingle penetration is used for the return and supply ducts (e.g., 61 and62) and the vertical or substantially vertical condensate drain line(e.g., 160). In the embodiment shown in FIGS. 2 and 11, drain line 161passes through conduit 1612 which is surrounded by insulation 1613. Inthis embodiment, conduit 1612 is supported by brackets 1615 and 1616from roof 4. In embodiments where a conduit (e.g., 1612 or 1622) isused, the conduit may facilitate installation by guiding the condensatedrain line (e.g., 161 or 162) through the roof curb (e.g., 45 shown inFIG. 6), the roof (e.g., 4), a roof penetration or hole (e.g., 44 shownin FIG. 2), or a combination thereof, for instance, after the unit isinstalled. The conduit, insulation, or both, may help to prevent thedrain line from freezing. In the embodiments illustrated, neither heatedair nor combustion gasses are circulated through conduit 1612 shown inFIGS. 2 and 11 or conduit 1622 shown in FIGS. 4, 6, 6 a, and 13. But inother embodiments, air from the space, combustion gasses (e.g., fromheat exchanger 300), or air heated by heat exchanger 300 may becirculated through such conduits (e.g., within an interstitial spacetherein between the conduit and drain line) to keep the drain line fromfreezing. In some embodiments, for example, the conduit may extend intothe space in the building and air from the space may be drawn throughthe conduit, through the interstitial space, for example, to the returnsection of the unit to warm the condensate drain line. In still otherembodiments, drain lines may be prevented from freezing or may be thawedusing an electrical resistance heating element or wire, as anotherexample.

FIGS. 22, 24, and 25 illustrate plug 203 that is installed in drain lineopening 1012 (i.e., in fitting 102) penetrating collector 101 in someembodiments in applications where the condensate passes through theinducer fan rather than through a drain line connected to drain lineopening 1012 (e.g., via fitting 102). As used herein, a cap isconsidered to be a type of “plug”. In the embodiment illustrated, plug203 both surrounds part of fitting 102 and extends inside of fitting102. In other embodiments, a plug may just fit inside the fitting oropening without surrounding part of the fitting or may just surroundpart of the fitting without fitting inside. Plug 203 is a press in (andon) plug and outside wall 2032 of plug 203 engages barbs 1022 on theoutside of fitting 102 while end 2031 of plug 203 fits inside fitting102. A person can install or remove plug 203 by grasping head 2033 byhand or with a tool such as pliers, for example. Other embodiments ofplugs (e.g., corresponding to plug 203) may be threaded, as anotherexample.

Further, as shown in FIG. 25, when the unit is properly installed, inembodiments and applications where plug 203 is used, end 2031 of plug203, is flush and level with horizontal inside bottom surface 1021 offitting 102, or substantially flush and level. This minimizes the amountof condensate (water) that collects within fitting 102 and reduced thechance that fitting 102 or collector 101 will be damaged if condensatetherein freezes. This configuration may also reduce the chance that suchfreezing will push plug 203 out of fitting 102 which would later spillcondensate inside the unit (e.g., onto floor 112 of enclosure 20 of unit2). In the embodiment illustrated, plug 203 is made of an elastomer andhas an interference fit with fitting 102. In other embodiments, the plugmay be plastic, such as PVC or polyethylene. Further, in the embodimentillustrated (e.g., in FIG. 25), a small layer of condensate may remainon bottom surface 1014 of collector 101 behind the bottom wall thicknessof fitting 102. This small layer of condensate could freeze,particularly if the unit is left off when ambient conditions aresufficiently below freezing. In the embodiment illustrated, however,this small layer of ice formation on bottom surface 1014 does not causea problem. Other embodiments, however, may be configured to avoid such asmall layer of condensate from remaining on the bottom surface (e.g.,1014) of the collector (e.g., 101), for instance, behind the bottom wallthickness of a fitting (e.g., 102) at the drain opening (e.g., 1012).

A number of embodiments include an exhaust conduit (e.g., 106, 506, orexhaust and drainage assembly 500) extending from the outlet (e.g., 105)of the inducer fan (e.g., 104) to the outside of the enclosure (e.g., 10or 20). In the embodiment shown, a coupling at outlet 105 connectsinducer fan 104 to pipe or exhaust conduit 106 or 506. See, for example,FIGS. 20-23. This coupling may be made of an elastomeric material (e.g.,a short section of hose) clamped to outlet 105 of inducer fan 104 and topipe or exhaust conduit 106 or 506), for example. Use of an elastomericmaterial for this coupling (e.g., at outlet 105) may reduce the transferof noise and vibration from inducer fan 104 to exhaust conduit 106 or506, for instance. In the embodiments shown in FIGS. 7-9, 14, and 22-25,condensate formed in condensing gas heat exchanger 300 passes fromcollector 101 through drain hole 1011 extending through collector 101 toinlet 1016 of the inducer fan 104. The condensate then travels throughinducer fan 104, through exhaust conduit 506 (part of exhaust anddrainage assembly 500), and out of enclosure 20 with the combustiongasses. Moreover, in this particular embodiment, the exhaust conduit orexhaust and drainage assembly 500 has a bifurcation 507 (e.g., a Tee)that separates the condensate from a majority of the combustion gasses.Further, the exhaust conduit, bifurcation 507 or exhaust and drainageassembly 500 includes a high path (e.g., 508 of assembly 500) and a lowpath (e.g., 57, for example, a drain line or hose attached via reducer511 and hose fitting 512, of assembly 500 in the embodiment shown).

In the embodiment illustrated, high path 508 of exhaust conduit orexhaust and drainage assembly 500 includes the vertical section of pipeshown, elbow 509, and horizontal pipe 510. Other embodiments may berouted differently. In a number of embodiments, however, such as theembodiment shown, the high path (e.g., 508 including 509 and 510) has alarger cross sectional area than the low path (e.g., 57), and themajority (i.e., by volume) of the combustion gasses pass through thehigh path (e.g., 508) when unit 2 is operating as a furnace. In theembodiment shown, a minority (i.e., by volume) of the combustion gassespass through low path 57 with the condensate. This minority of thecombustion gasses may keep the condensate within low path 57 fromfreezing when ambient temperature conditions are below freezing bywarming low path 57 of exhaust and drainage assembly 500. In someembodiments, such as shown in FIGS. 22 and 23, insulation 56 furtherhelps to keep low path or drain line 57 warm to prevent condensatetherein from freezing. In a number of embodiments, the low path (e.g.,57) may have a continually downward gradient, for example, so thatcondensate does not collect in the low path and freeze when the unit orfurnace is not operating and when ambient temperature conditions arebelow freezing.

In the embodiment shown in FIGS. 7-9 and 22-23, low path 57 dischargesinto vertical standpipe 54. As used herein, unless stated otherwise, a“vertical standpipe” is vertical to within ten degrees. In otherembodiments, a “substantially vertical standpipe” is vertical to within15 degrees. In still other embodiments, a standpipe may be vertical towithin 7.5, 5, 4, 3, 2, or 1 degrees, as other examples. In theembodiment shown, vertical standpipe 54 is substantially larger indiameter, cross-sectional dimension, or cross-sectional area than lowpath 57. As used herein, “substantially larger in diameter means havingat least twice the diameter, and substantially larger in cross-sectionalarea means having at least four times the cross-sectional area. As shownin FIGS. 22 and 23, insulation 56 on low path 57 has a smaller outsidediameter than the inside diameter of standpipe 54. In a number ofembodiments, the condensate is allowed to drip into vertical standpipe54 from low path 57. As shown in FIGS. 22 and 23, in a number ofembodiments, low path 57 extends into stand pipe 54 and the minority ofthe combustion gasses emerging from low path 57 into standpipe 54 areexhausted upward between low path 57 and standpipe 54 (e.g., between theoutside of insulation 56 and the inside of standpipe 54). In someembodiments, this upward flow of warm exhaust gas (i.e., combustiongasses) further warms low path 57 and the inside of standpipe 54, in theembodiment shown, preventing the condensate therein from freezing.Further, in the embodiment shown, exhaust and drainage assembly 500 isattached to enclosure 20 for support via mounting bracket 521 andU-bolts 522 and 523 shown, for example, in FIGS. 22 and 23.

As shown in FIGS. 7-9, in various embodiments, unit 2 is installed atground level (e.g., on a concrete slab located on the ground, forinstance, at ground level 80 shown in FIG. 9) and standpipe 54 extendsinto the ground and terminates with at least one opening (e.g., holes 52shown in FIG. 8) to the ground. In a number of embodiments, this openingmay be, for example, below the frost line (e.g., 81) in the ground.Furthermore, in a number of embodiments, the condensate is directed todischarge into a bed of neutralizing media or porous alkaline material82, such as limestone, which may have been placed in the ground toneutralize acidity of the condensate. The condensate may percolate fromthis porous bed (e.g., 82) into the ground. As shown in FIG. 7, in someembodiments, standpipe 54 is a straight plain end pipe that simplyterminates (e.g., below the frost line) in the ground or in the bed ofneutralizing media or porous alkaline material (e.g., 82). Suchembodiments may be suitable for sandy or porous soils, for example. Asshown in FIG. 8, however, in other embodiments, standpipe 54 connects toa horizontal pipe (e.g., below the frost line) in the ground or in thebed of neutralizing media or porous alkaline material (e.g., 82), thatcontains multiple openings (e.g., holes). Perforated sleeve or pipe 52shown in FIG. 8 is an example of such a horizontal pipe, which isconnected to standpipe 54 with elbow 53. Perforated sleeve or pipe 52,standpipe 54, and elbow 53 may be plastic pipe, and may be made of athermoplastic, such as PVC, polyethylene, or ABS (acrylonitrilebutadiene styrene), as examples.

In still other embodiments, standpipe 54 may connect to a trap below thefrost line, and then into a sewer or septic system. Further, in certainembodiments, unit 2 may be installed on a roof and standpipe 54 mayextend into a building, for example, for disposal into a sewer or septicsystem. Precautions may be advisable, however to prevent the minority ofthe combustion gasses that passes through the low path (e.g., 57) fromentering a sewer, building, or other enclosed space where a sufficientlyhigh concentration of combustion gasses (i.e., carbon dioxide) may posea hazard to occupants. For this reason, the condensate drain lineconfigurations illustrated in FIGS. 1-6, 11-13, 15-19, and 28-29 may bebetter for installations that drain condensate into a building or into asewer. In the embodiments of FIGS. 1-6, 11-13, 15-19, and 28-29, sincethe condensate is taken from collector 101 on the suction side ofinducer fan 104, any failure of a trap or drain line (e.g., with in thebuilding or occupied space) would result in indoor air (e.g., fromwithin the building) or sewer gasses (e.g., from the sewer that thedrain line drains into) being drawn up the drain line into the collectorrather than combustion gasses flowing out of the drain line into thebuilding or sewer.

As illustrated, the embodiments of FIGS. 1-6, 11-13, 15-19, and 28-29,in which the condensate is taken from collector 101 on the suction sideof inducer fan 104, may include a trap to prevent air from within thebuilding or sewer gasses from traveling up through the drain line tocollector 101 and out through inducer fan 104. The trap also avoidshaving a higher static pressure within the drain line (e.g., at or justbelow drain line opening 1012), that may interfere with drainage ofcondensate from collector 101 into the drain line (e.g., through drainline opening 1012). By preventing air from within the building or sewergasses from traveling up through the drain line and into the collector,the trap prevents such a flow of air from blowing condensate away fromdrain line opening 1012, which may interfere with proper drainage fromcollector 101. In some embodiments, the trap is formed using a S shapeor a loop in the drain line itself. Examples include trap 1601 in drainline 160 in FIGS. 1, 3, and 12; trap 1611 in drain line 161 in FIGS. 2and 11; trap 1621 in drain line 162 in FIGS. 4, 5, and 13; trap 1641 inFIGS. 16, 19, 28, and 30; and trap 1651 in FIG. 17. In the embodimentshown in FIGS. 1-4 and 11-13, for example, the trap is formed by makinga loop in the tubing (i.e., drain line) and securing the loop with tie1610. Tie 1610 may be metal or plastic, for example, and may form a loopor S shape, for example. Other embodiments may use a molded loop or Strap, as other examples.

In many embodiments that have a trap and have the condensate drain lineconnected to the collector (e.g., 101) on the suction side of theinducer fan (e.g., 104), if there is not sufficient water in the trap,or if there is a breach in the drain line above the trap within thebuilding, for example, air or sewer gasses would flow from within thebuilding into the collector (e.g., 101) and out of the unit through theinducer fan (e.g., 104) and the exhaust conduit (e.g., 106), rather thancombustion gasses from the heat exchanger (e.g., 300) and collector(e.g., 101) flowing into the building or sewer. If there is no water inthe trap, airflow through the drain line may partially or fully preventcondensate from flowing through the drain line until the unit cyclesoff. When the unit cycles off, however, and the inducer fan (e.g., 104)turns off, condensate may flow from the collector though the drain lineand fill the trap. Once the trap contains sufficient water (condensate)to prevent airflow though the drain line, in a number of embodiments,condensate will flow through the drain line unimpeded by airflow in anopposite direction.

Further, certain embodiments are or include a particular apparatus forpassing a tube through a wall of a duct, for forming a trap with thetube, or both. Examples (e.g., apparatus 150 and 170) are illustrated inFIGS. 16, 17, 19, and 28. In the embodiments illustrated, apparatuses150 and 170 each include, for example, plate 155 or 175 having bend 156or 176 extending across the plate (e.g., 155 or 175). In a number ofembodiments, the bend (e.g., 156 or 176) may separate the plate (e.g.,155 or 175) into a first portion (e.g., 157 or 177) and a second portion(e.g., 158 or 178). Plates 155 and 175 may be made of sheet metal, in anumber of embodiments, for example, galvanized steel, aluminum, oraluminized steel, which may be cold bent at bend 156 or 176. In otherembodiments, as another example, plates 155 and 175 may be made ofplastic, which may be formed or molded with bend 156 or 176 therein. Ineither of such embodiments, the first portion (e.g., 157 or 177) isconnected to the second portion (e.g., 158 or 176) at the bend (e.g.,156 or 176).

In various embodiments, the first portion (e.g., 157 or 177) is at anon-zero angle to the second portion (e.g., 158 or 178), also at thebend (e.g., 156 or 176). As used herein, a non-zero angle is an angle offive degrees (measured from being straight) or more. Such a bend may bea sharp bend or may formed by curvature or multiple sharp bends, asexamples. In a number of embodiments, for example, where the bend isformed by curvature or multiple sharp bends, the bend may extend over adimension of the plate that is less than a particular fraction of anoverall dimension of the plate (e.g., 155 or 175). That overalldimension may be length or width of the plate or length or width of thefirst portion (e.g., 157 or 177) or the second portion (e.g., 158 or178), as examples. In certain embodiments, for instance, the fractionmay be 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50 percent of theoverall dimension, as examples.

In the embodiment shown, the non-zero angle at the bend (e.g., bend 156or 176) is a right angle or a 90-degree bend. As used herein, a rightangle is 90 degrees plus or minus 10 degrees. In other embodiments, thenon-zero angle at the bend (e.g., bend 156 or 176) may be, for example,10, 20, 30, 40, 50, 60, 70, 80, 85, 95, 100, 110, 120, 130, or 135degrees, as examples, each plus or minus 5 degrees, measured fromstraight (no bend). In certain embodiments, the non-zero angle at thebend (e.g., bend 156 or 176) may be, for instance, between 45 degreesand 135 degrees, between 60 degrees and 120 degrees, between 70 degreesand 110 degrees, between 75 degrees and 105 degrees, or between 80 and100 degrees, as examples.

In the embodiments illustrated, for example, in FIGS. 16 and 17, firstportion 155 or 175 has first hole 151 sized and shaped for passage ofthe tube (e.g., condensate drain line 164 or 165). Hole 151 may be roundor elliptical, for example, and may have an inside diameter that isequal to or slightly greater than an outside diameter of the tube (e.g.,condensate drain line 164 or 165). In certain embodiments, however, hole151 may have an inside diameter that is equal to or slightly less thanan outside diameter of the tube (e.g., condensate drain line 164 or165), thus creating an interference fit with the tube and avoidingleakage (e.g., of air) between the tube and hole 151. Such aninterference fit, however, may make installation of the tube difficult.For this reason, a slight clearance fit may be preferable, in a numberof embodiments.

Further, in the embodiments shown, second portion 158 or 178 has secondhole 152 sized and shaped for passage of the tube (e.g., condensatedrain line 164 or 165) and third hole 153, also sized and shaped forpassage of the tube. Holes 152 and 153 may be sized and shaped asdescribed above for hole 151, for example. In the case of holes 152 and153, however, avoiding leakage between the inside of the hole and thetube may not be a consideration. But a sufficiently close fit or even aninterference fit, in some embodiments, may be beneficial to hold thetube in position to form loop or trap 1641 or 1651. In some embodiments,the tube may be held in place (e.g., to form loop or trap 1641 or 1651)with a clamp, an adhesive, tape, a grommet, or a combination thereof, asexamples.

Moreover, in the embodiments shown, first portion 157 or 177 also hasmultiple fourth holes 154 which are sized and shaped for passage offasteners. Such fasteners may be sheet metal screws, for instance thatpass through the multiple fourth holes 154 and screw into the wall ofthe duct (e.g., 63 or 73) from the outside of the duct to attach thefirst portion 157 or 177 to the duct. In other embodiments, on the otherhand, the fasteners, or other fasteners described herein, may be clips(e.g., push clips, which may be plastic or metal wire, as examples), orpop rivets, for instance, and may attach to the wall of the duct (e.g.,63 or 73). Further, each of the multiple fourth holes 154 may besubstantially smaller in diameter than first hole 151, second hole 152,third hole 153, or a combination thereof. In this context, substantiallysmaller in diameter means half of the diameter or less. In theembodiment illustrated, first portion 157 and first portion 177 eachhave four fourth holes 154. Further, in the embodiment illustrated,first portion 157 and first portion 177 are each rectangular and haveone of the fourth holes 154 in each corner. Other embodiments may have1, 2, 3, 5, 6, 7, 8, 9, 10, or 12 fourth holes that are sized and shapedfor passage of fasteners, as other examples. Still other embodiments mayhave one or more tabs that fit inside the duct (e.g., 63 or 73) at oneend of the first portion (e.g., 157 or 177) and one or multiple fourthholes 154 that are sized and shaped for passage of one or more fastenersat the other end. Even further, some embodiments may have tabs at bothends. Other embodiments may attach with an adhesive, with a clamp, orwith tape, as other examples.

Furthermore, in the embodiment shown, the first portion (e.g., 157 or177) of the apparatus (e.g., 150 or 170) is configured to seal anopening (e.g., access opening 631 shown in FIG. 19) in the wall of theduct (e.g., 63 or 73 in FIGS. 16 and 17) by placing the first portion(e.g., 157 or 177) over the opening (e.g., 631) with the second portion(e.g., 158 or 178) outside of the duct (e.g., 63 or 73) and attachingthe first portion (e.g., 157 or 177) to the duct (e.g., 63 or 73), forinstance, with multiple fasteners that pass through the multiple fourthholes (e.g., 154) and attach to (e.g., screw into) the wall of the duct(e.g., 63 or 73). Moreover, in the embodiment shown, the first portion(e.g., 157 or 177) is actually performing the function of sealing theopening (e.g., 631) in the duct (e.g., 63 or 73). In these embodiments,the first portion (e.g., 157 or 177) is configured to seal an opening(e.g., 631) in the wall of the duct (e.g., 63 or 73) by having a shapethat corresponds to the opening (e.g., both being flat or planar) and bybeing large enough to cover the opening (e.g., 631) and allow space forfasteners to be used through holes 154. In some embodiments, the firstportion may be further configured with a gasket or adhesive to provide abetter seal. Further, in some embodiments, the first portion and theopening (e.g., 631) in the wall of the duct may both be rectangular. Inother embodiments, however, the first portion may be rectangular and theopening (e.g., 631) in the wall of the duct may be round, rectangularwith rounded corners, square, or oval, as other examples.

Even further, in the embodiments illustrated, apparatuses 150 and 170are configured to permit the tubing (e.g., condensate drain line 164 or165) to penetrate the wall of the duct (e.g., 63 or 73) though firsthole, then bend downward through second hole 152, and then bend upward,looping substantially 360 degrees around, to extend downward throughthird hole 153, forming helical loop 1641 or 1651 in the tubing (e.g.,164 or 165) with (i.e., the loop having) a substantially horizontalaxis. In the embodiments shown, this loop 1641 or 1651 serves as a trapin the tubing (e.g., condensate drain line 164 or 165), for example,preventing air, combustion gasses from the furnace (e.g., HVAC unit 1),or sewer gasses from passing through the tubing (e.g., condensate drainline 164 or 165). As mentioned, such a trap (e.g., loop 1641 or 1651)also avoids the formation of a higher static pressure within the drainline (e.g., condensate drain line 164 or 165, for instance, below drainline opening 1012) that would interfere with proper drainage fromcollector 101, through drain line opening 1012, into the drain line(e.g., condensate drain line 164 or 165). In other embodiments, a trapmay be formed in with a different number of holes in the apparatus, suchas 2 or 4 holes. For instance, in some embodiments the tube may passsubstantially horizontally through the first hole in the apparatus, andthen may bend upward looping substantially 270 degrees around to extenddownward through the second or third hole forming helical loop in thetubing with a substantially horizontal axis. As another example, in someembodiments the tube may pass substantially horizontally through thefirst hole in the apparatus, and then may bend upward loopingsubstantially 270 degrees around to extend downward through the secondhole, and then may bend upward, looping substantially 360 degreesaround, to extend downward through third hole, forming two helical loopsin the tubing with a substantially horizontal axis.

Moreover, in the embodiments depicted, the first portion (e.g., 157 or177) is larger than the second portion (e.g., 158 or 178). Additionally,some embodiments further include, for example, a first grommet at firsthole 151, a second grommet at second hole 152, a third grommet at thirdhole 153, or a combination thereof. In a number of embodiments, thefirst grommet, the second grommet, the third grommet, or a combinationthereof, are (e.g., all) configured to protect the tubing (e.g.,condensate drain line 164 or 165) from being damaged by edges of firsthole 151, second hole 152, or third hole 153. The grommets may be soconfigured by having surfaces that contact the tubing that are larger orless sharp than holes 151, 152, and 153, for example. The grommets mayalso (or instead) provide a better seal around the tubing (e.g., atfirst hole 151) may help to grip the tubing better (e.g., at third hole153), or a combination thereof. Such grommets may be plastic, forexample. In some embodiments, the grommets may be made of an elastomericmaterial or rubber. An example of a grommet is grommet 1636 shown inFIG. 6 a. The grommets at holes 151, 152, and 153 may be the same as orsimilar to grommet 1636, for example.

Furthermore, some embodiments may further include the tubing (e.g.,condensate drain line 164 or 165), for example, which passes thoughfirst hole 151, then bends and passes through second hole 152, and thenbends and loops 360 degrees around to extend through third hole 153forming the helical loop (e.g., 1641 or 1651). In the embodiments shownand described, the tubing is a drain line (e.g., condensate drain line164 or 165) for the HVAC unit (e.g., 1) and the tubing extends from theHVAC unit, through the duct (e.g., 63 or 73), and penetrates the wall ofthe duct though first hole 151, then bends downward through second hole152, and then bends upward looping substantially 360 degrees around, andthen extends downward through third hole 153 forming the helical loop inthe tubing with a substantially horizontal axis that serves as a trap inthe tubing. Still further, in some embodiments, the apparatus mayinclude, for example, the HVAC system including, for instance, the duct(e.g., 63 or 73), the HVAC unit (e.g., HVAC unit 1), or both. In theembodiments shown, duct 63 and 73 are return ducts delivering air to theHVAC unit. Further, ducts 63 and 73 are the ducts that have the wallthat has the opening (e.g., 631 shown in FIG. 19) that is sealed byfirst portion 157 or 177 of the apparatus (e.g., 155 or 175) with secondportion 158 or 178 outside of the duct.

Further, the embodiments in which the condensate is taken from thecollector (e.g., 101) on the suction side of inducer fan (e.g., 104),may be installed at ground level in some applications. For example, FIG.17 illustrates an embodiment in which horizontal ducts 73 and 72 connectthe unit to the building. In the embodiment illustrated, condensatedrain line 165 is routed through return duct 71 and 73. In thisparticular embodiment, drain line 165 exits duct 73 at a distance fromthe unit. Such an exit may be within the building, for example, toprevent trap 1651 from freezing. In other embodiments, the condensatedrain line and trap may be kept from freezing in another way. Examplesinclude locating the trap in the duct or heating the trap to preventfreezing. In some embodiments, the trap may be allowed to freeze if theHVAC unit is not used for a long period, but may be located within theduct (e.g., in return duct 73) or heated sufficiently that the trap willthaw quickly when the unit is started. In climates where freezingoccurs, however, the trap frequently used in embodiments that drain thecondensate from drain opening 1012 in collector 101 poses a freezingrisk that is not found in embodiments such as air conditioning unit 2shown in FIGS. 7-9, 14, and 22-23. For this reason, the embodiment shownin FIGS. 7-9, 14, and 22-23 may be preferable for discharging condensateinto the ground in climates where freezing is a concern.

As mentioned previously, in a number of embodiments, HVAC units areconfigured for installation at ground level and are also configured forinstallation on a roof of a building. For example, HVAC units 1, 2, or 3that include collector 101 shown in FIGS. 20-25 are configured forinstallation at ground level (e.g., 80 shown in FIG. 9) and are alsoconfigured for installation on a roof (e.g., 4 shown in FIGS. 1-6) of abuilding. As shown in FIGS. 1-6, 10-13, 15-21, and 28-31, unit 1 or 3can be installed on a roof of a building by attaching a drain line 160,161, 162, 163, 164, or 165, to drain line opening 1012 penetratingcollector 101 (e.g., using fitting 102) and routing the drain line fordisposal into a sewer (e.g., as described, in a number of embodiments,herein). Thus, HVAC unit 1 is configured for installation on a roof of abuilding at least, for example, by providing drain line opening 1012penetrating collector 101. In some embodiments, HVAC unit 1 is furtherconfigured for installation on a roof of a building by providing othercomponents or adaptations described herein, such as the drain line(e.g., 163 shown in FIG. 10), a conduit for the drain line (e.g., 1622shown in FIGS. 6 and 13, 1612 shown in FIG. 11, or 135 shown in FIGS.10, 15-18, and 28-31), a hole in the floor (e.g., 112) of the enclosure(e.g., 10) for a drain line or drain line conduit (e.g., hole 1635 shownin FIGS. 6, 6 a, and 11-13), other components described herein usedspecifically for installation on a roof (e.g., 4), or a combinationthereof.

Moreover, HVAC units 1, 2, or 3 that include collector 101 shown inFIGS. 20-25 are also configured for installation at ground level (e.g.,80 shown in FIG. 9) by installing or leaving installed plug 203 (e.g.,shown in FIGS. 24 and 25) in fitting 102, or the combination thereof indrain line opening 1012 of collector 101, and allowing condensate topass through drain hole 1011 (shown, for example, in FIGS. 21, 23, and24) extending through collector 101 to the inlet (e.g., 1016) of inducerfan 104. The condensate may then travel through inducer fan 104, throughexhaust conduit 506 (e.g., part of exhaust conduit or exhaust anddrainage assembly 500), and out of the enclosure (e.g., 20) with thecombustion gasses. Thus, the HVAC unit (e.g., 1 or 2) is configured forinstallation at ground level (e.g., 80 shown in FIG. 9) at least, forexample, by providing drain hole 1011 extending through collector 101 tothe inlet (e.g., 1016) of inducer fan 104. Other embodiments may beconfigured for installation at ground level by allowing condensate topass into inducer fan 104 via exhaust hole 1013 for inducer fan 104, asanother example. In some embodiments, HVAC unit 2 is further configuredfor installation at ground level by providing other components oradaptations described herein, such as plug 203, tee or bifurcation 507,high path 508 and low path 57, standpipe 54, or the bed of neutralizingmedia or porous alkaline material 82.

As mentioned, in some embodiments, when air conditioning unit 1 or 2 isinstalled and leveled properly in accordance with the manufacturer'sinstallation instructions, drain hole 1011 is higher than drain lineopening 1012. In certain embodiments, drain hole 1011 acts as anoverflow for drain line opening 1012. Thus, if drain line opening 1012,fitting 102, the drain line (e.g., 160, 161, 162, 163, 164, or 165) isplugged, the unit may still operate, but condensate may pass throughdrain hole 1011 and inducer fan 104, and may be exhausted with thecombustion gasses. Depending on the routing of the drain line, underfreezing conditions, the drain line may be plugged with frozencondensate, for example, and may unplug on its own later when ambienttemperatures increase. Further, in some embodiments, the drain line mayfreeze when the unit is turned off for an extended period undersufficiently cold conditions, but may thaw out after the unit has beenoperating in a heating mode for a sufficient period of time, as anotherexample.

When drain hole 1011 acts as an overflow, and condensate is not able todrain though opening 1012, if ambient conditions are below freezing, icemay form beside the unit, for example, on the roof or on the ground. Ifsuch ice only forms for a short time, however, such ice formation maynot be problematic. In some instances, the ice formation, or water ifconditions are warmer, may serve to warn the owner or user of the unitthat the drain line is plugged. Further, some embodiments may omit drainhole 1011, and instead, exhaust hole 1013 for inducer fan 104, mayperform the role of drain hole 1011. In the embodiment illustrated,exhaust hole 1013 is also higher than drain line opening 1012 andextends through collector 101 to inlet 1016 of inducer fan 104. Thus, insuch embodiments, exhaust hole 1013 may act as an overflow for drainline opening 1012. Further, in embodiments that have a drain hole 1011,exhaust hole 1013 may act as an overflow for drain hole 1011. Inembodiments that have a drain hole 1011, however, drain hole 1011 mayreduce the amount of condensate that will accumulate in the collector(e.g., in collector 101 with plug 203 installed in drain line opening1012 rather than a drain line attached thereto). An accumulation ofcondensate in the collector could freeze, for example, if the unit isturned off for an extended period when ambient conditions aresufficiently below freezing.

Still other embodiments include particular methods, for example, ofreducing consumption of fossil fuels, of reducing emission of greenhousegasses, or both, for instance. Such reductions may be significant, forexample, because they are from HVAC equipment that is widely used. FIG.32 illustrates an example of such a method, method 320, of reducingconsumption of fossil fuels from widely used HVAC equipment (e.g., airconditioning units with gas furnaces or gas package units). Method 320includes certain acts that are shown in FIG. 32, described herein, orboth, which may be performed in the order indicated or in another order.These acts may include, for example, act 325 of manufacturing,obtaining, or providing air conditioning units that have condensing heatexchangers, act 326 of advertising installation options, and act 327 ofinstructing installers of the air conditioning units regardinginstallation of those units and condensate disposal. Various embodimentsmay include some or all of these acts.

In a number of embodiments, act 325 includes manufacturing, obtaining,or providing air conditioning units with condensing (e.g., gas) heatexchanger such as units 1, 2, or 3 described herein, for example.Further, in various embodiments, act 326 may include advertising thatthe air conditioning units (e.g., with condensing heat exchangers) canbe installed on a roof of a building and condensate from the condensinggas heat exchangers (e.g., 300) can be disposed of by routing a drainline (e.g., 160, 161, 162, 163, 164, or 165) through the roof (e.g., 4)of the building for disposal, for example, inside the building.Moreover, in many embodiments, act 326 may include advertising that theair conditioning units can be installed at ground level (e.g., 80 shownin FIG. 9 or on slab 5 shown in FIGS. 7-9) and condensate from thecondensing gas heat exchangers (e.g., 300) can be disposed of into theground (e.g., via standpipe 54 shown in FIGS. 22 and 23). Advertisingmay be performed, for example, using sales persons, through printedmaterial or sales literature, through one or more Internet websites,through Internet advertisements displayed on websites of others, byblogging on the Internet, by direct mail, by e-mail, in catalogues,through broadcast media such as radio or television, on YouTube, throughInternet-based networking sites such as Facebook or LinkedIn, throughprinted periodicals such as magazines or newspapers, via onlineperiodicals, by telephone, via call centers, through distributors, or onproduct packaging, as examples, or a combination thereof.

In some embodiments, the act (e.g., 325) of manufacturing, obtaining, orproviding the air conditioning units (e.g., 1, 2, or 3) includesmanufacturing, obtaining, or providing air conditioning units thatinclude a condensing (e.g., gas) heat exchanger (e.g., 300 shown in FIG.26) having at least one stage (e.g., stage 312) that has fins, acollector (e.g., 101 shown in FIGS. 20-24) connected to the (e.g., atleast one) stage (e.g., 312) that has fins, and an inducer fan (e.g.,104 shown in FIGS. 20-23) having an inlet (e.g., 1016) connected to thecollector (e.g., 101). In a number of embodiments, the collector (e.g.,101) has a drain line opening (e.g., 1012) penetrating the collector.Moreover, in particular embodiments, act 325 of manufacturing,obtaining, or providing the air conditioning units includesmanufacturing, obtaining, or providing units that include a drain hole(e.g., 1011) extending through the collector (e.g., 101) to the inlet(e.g., 1016) of the inducer fan (e.g., 104). In a number of embodiments,the drain hole (e.g., 1011) is higher (e.g., when the unit is properlyinstalled and level) than the drain line opening (e.g., 1012).

Further, in some embodiments, act 327 includes instructing an installerof the units that when they install the unit at ground level (e.g., 80shown in FIG. 9) and dispose of condensate from the condensing gas heatexchanger into the ground (e.g., as shown in FIGS. 7-9 and 14), thatthey can leave in place, or install, a plug (e.g., plug 203 shown inFIGS. 22, 24, and 25) in the drain line opening (e.g., 1012, or infitting 102) penetrating the collector (e.g., 101) and allow thecondensate to pass through the inducer fan (e.g., 104). As used herein,instructing (e.g., in act 327) an installer that they “can” do a certainact includes doing one or both of: instructing the installer to performthe act, or instructing the installer that performing the act is anoption. Further, as used herein, instructing (e.g., in act 327) aninstaller that they “can” provide certain components or a particularconfiguration includes doing one or more of: instructing the installerto provide the certain components or the particular configuration,instructing the installer that providing the certain components or theparticular configuration is an option, or showing the certain componentsor the particular configuration in an illustration such as a drawing,picture, or video.

Moreover, in some embodiments act 327 includes instructing an installerof the units that when they install the unit on the roof (e.g., 4) ofthe building and dispose of condensate from the condensing (e.g., gas)heat exchanger (e.g., 300), for instance, in the building (e.g., asshown, in different embodiments, in FIGS. 1-6, 11-13, 15-19, and 28-29),that they can leave attached, or attach, the drain line (e.g., 160, 161,162, 163, 164, or 165) to the opening (e.g., 1012, or to fitting 102)penetrating the collector (e.g., 101). In some embodiments, act 327 mayalso include instructing the installer that they can route the drainline (e.g., 160, 161, 162, 163, 164, or 165) through the roof (e.g., 4),and allow the condensate to pass through the drain line for disposalinside the building. In various embodiments, an installer may beinstructed (e.g., in act 327) via written instructions provided with theunit, though a website, by e-mail, through an instructional video, byinstructions provided on product packaging, through training classes,through a technical service call center, or a combination thereof, asexamples. Further, although shown in FIG. 32 as one act 327, variousinformation conveyed to installers may be conveyed in the same orseparate acts, in different embodiments. Still further, variousinformation described herein as being conveyed to installers in separateacts may be conveyed in the same act.

Even further, in some embodiments act 327 includes instructing aninstaller of the units that when they install the unit on the roof(e.g., 4) of the building and dispose of condensate from the condensinggas heat exchanger in the building, that they can provide a trap (e.g.,1601, 1611, 1621, 1641 or 1651 shown in FIGS. 1-4, 11-13, 16, 17, 19,28, and 30) in the drain line (e.g., 160, 161, 162, or 164) inside thebuilding. In embodiments where a drain line is attached to the collector(e.g., 101, at opening 1012, for instance, via fitting 102) the trap maykeep air from within the building or sewer gasses from traveling upthrough the drain line and out through the inducer fan (e.g., 104). Airor sewer gasses traveling up through the drain line and out through theinducer fan (e.g., 104) may prevent condensate from draining through thedrain line, in some embodiments.

Still further, in some embodiments act 327 may include instructing aninstaller of the units that when they install the unit on the roof(e.g., 4) of the building and dispose of condensate from the condensing(e.g., gas) heat exchanger (e.g., 300) in the building, that they caninstall the unit on a roof curb assembly (e.g., 45 shown in FIG. 6) androute the drain line (e.g., 162) through a tubular conduit (e.g., 1622)that passes through the roof curb assembly and through the roof of thebuilding. Further, in certain embodiments, act 327 may includeinstructing an installer of the units that when they install the unit onthe roof of the building and dispose of condensate from the condensinggas heat exchanger in the building, that they can route the drain line(e.g., 163 or 164) through the roof (e.g., 4) of the building inside ofa return duct (e.g., 63) that connects to the unit to deliver air fromwithin the building to the unit. Examples of such a configuration areshown in FIGS. 16, 18, 19, and 28-31).

In a number of embodiments, act 325 of manufacturing, obtaining, orproviding the air conditioning units includes manufacturing, obtaining,or providing air conditioning units that include a return duct opening(e.g., 296 or 171 shown in FIGS. 10-19, 28, and 29) for connecting theunit to a return duct (e.g., 61, 63, or 71)) that delivers air to theunit (e.g., 1 or 2) from the building. In particular embodiments, thedrain line (e.g., 163, 164, or 165) is connected to the unit (e.g., toopening 1012 or fitting 102) to receive the condensate and the drainline extends to the return duct opening (e.g., 296 or 171) and is storedat the return duct opening during shipment of the unit (e.g., as shownin FIGS. 10 and 15). This configuration may be, for instance, forrouting the drain line (e.g., 163, 164, or 165) through the return duct(e.g., 61, 63, or 71) when the unit is installed on the roof (e.g., 4)of the building. Further, in some embodiments, act 325 of manufacturing,obtaining, or providing the air conditioning units may includemanufacturing, obtaining, or providing air conditioning units thatinclude (e.g., besides the return duct opening, such as 296 or 171, forconnecting the unit to a return duct, such as 61, 63, or 71, thatdelivers air to the unit from the building) a tubular conduit (e.g., 135shown in FIGS. 15-18 and 28-31 that extends to the return duct opening(e.g., 296 or 171). This conduit (e.g., 135) may be for routing thedrain line (e.g., 164 or 165) through the return duct (e.g., 63 or 71)when the unit is installed on the roof (e.g., 4) of the building or whenthe unit is mounted at ground level (e.g., 80), as examples.

Some embodiments may further include, for example, in act 327,instructing an installer of the units (e.g., 2) that when they installthe unit at ground level (e.g., as shown in FIGS. 7-9) and dispose ofcondensate from the condensing (e.g., gas) heat exchanger (e.g., 300)into the ground, that they can install a bifurcation (e.g., 507 shown inFIGS. 22 and 23) in an exhaust conduit or exhaust and drainage assembly(e.g., 500) extending from an outlet (e.g., 105) of an inducer fan(e.g., 104) of the unit to outside of an enclosure (e.g., 20 shown inFIGS. 7-9) for the unit. In a number of embodiments, this act (e.g., act327 or part thereof) may include instructing that the bifurcation (e.g.,507) can be installed to provide a high path (e.g., 508) and a low path(e.g., 57), and that the low path can be installed to discharge into avertical standpipe (e.g., 54), for instance. Further, certainembodiments may include, for example, in act 327, instructing theinstaller of the units that when they install the unit at ground level(e.g., as shown in FIGS. 7-9) and dispose of condensate from thecondensing gas heat exchanger into the ground, that they can provide alow path (e.g., 57) that discharges into a vertical standpipe (e.g., 54)that extends into the ground and terminates with at least one opening(e.g., 52) to the ground below a frost line (e.g., 81) in the ground.Still further, some embodiments may further include, for example, in act327, instructing an installer of the units that when they install theunit at ground level (e.g., 80 shown in FIG. 9) and dispose ofcondensate from the condensing gas heat exchanger into the ground, thatthey can direct the condensate to discharge into a bed of porousalkaline material (e.g., 82) in the ground, for example, to neutralizeacidity of the condensate.

Various methods may further include acts of obtaining, providing, ormaking various components described herein or known in the art. Otherembodiments include a building that includes an air conditioning unit orHVAC unit or system described herein. Various methods in accordance withdifferent embodiments include acts of selecting, making, positioning, orusing certain components, as examples. Other embodiments may includeperforming other of these acts on the same or different components, ormay include fabricating, assembling, obtaining, providing, ordering,receiving, shipping, or selling such components, or other componentsdescribed herein or known in the art, as other examples. Further,various embodiments include various combinations of the components,features, and acts described herein or shown in the drawings, forexample. Further, particular embodiments include various means foraccomplishing one or more of the particular functions described hereinor apparent from the structure described. Other embodiments may beapparent to a person of ordinary skill in the art having studied thisdocument.

1. An air conditioning unit packaged with a condensing gas heatexchanger, the unit comprising: an enclosure; a return duct opening forconnecting the unit to a return duct that delivers air to the unit fromthe space; a supply duct opening for connecting the unit to a supplyduct that delivers air from the unit to the space; the condensing gasheat exchanger for heating the air; a collector connected to thecondensing gas heat exchanger; an inducer fan having an inlet connectedto the collector and an outlet; and an exhaust conduit extending fromthe outlet of the inducer fan to outside of the enclosure; wherein thecollector further comprises: an exhaust hole for the inlet of theinducer fan; and a drain hole extending through the collector to theinlet of the inducer fan; wherein: the drain hole is lower than theexhaust hole for the inducer fan; the drain hole has a smallercross-sectional area than the exhaust hole for the inducer fan; andcondensate formed in the condensing gas heat exchanger passes throughthe drain hole to the inlet of the inducer fan, through the inducer fan,and into the exhaust conduit with combustion gasses.
 2. The airconditioning unit of claim 1 wherein: the exhaust conduit comprises abifurcation that separates the condensate from a majority of thecombustion gasses; the bifurcation comprises a high path and a low path;the high path has a larger cross sectional area than the low path; themajority of the combustion gasses pass through the high path; and aminority of the combustion gasses pass through the low path with thecondensate to keep the condensate from freezing when ambient temperatureconditions are below freezing.
 3. The air conditioning unit of claim 2further comprising a vertical standpipe wherein the low path dischargesinto the vertical standpipe and the condensate is allowed to drip intothe vertical standpipe while the minority of the combustion gassesemerging from the low path are exhausted upward between the low path andthe standpipe.
 4. The air conditioning unit of claim 3 wherein thestandpipe extends into the ground and terminates with at least oneopening to the ground below a frost line in the ground.
 5. The airconditioning unit of claim 1 further comprising a bed of porous alkalinematerial in the ground wherein the condensate is directed to dischargeinto the bed of porous alkaline material in the ground to neutralizeacidity of the condensate and dispose of the condensate into the ground.6. An air conditioning unit packaged with a condensing gas heatexchanger, the unit comprising: an enclosure; a return duct opening forconnecting the unit to a return duct that delivers air to the unit fromthe space; a supply duct opening for connecting the unit to a supplyduct that delivers air from the unit to the space; the condensing gasheat exchanger for heating the air; a collector connected to thecondensing gas heat exchanger; an inducer fan having an inlet connectedto the collector and an outlet; and an exhaust conduit extending fromthe outlet of the inducer fan to outside of the enclosure; wherein: thecollector further comprises an exhaust hole for the inlet of the inducerfan; and condensate formed in the condensing gas heat exchanger passesthrough the inducer fan, into the exhaust conduit, and out of theenclosure; the exhaust conduit comprises a bifurcation that separatesthe condensate from a majority of the combustion gasses; the bifurcationcomprises a high path and a low path; the high path has a larger crosssectional area than the low path; and the majority of the combustiongasses pass through the high path.
 7. The air conditioning unit of claim6 wherein the low path has a continually downward gradient and aminority of the combustion gasses pass through the low path with thecondensate to keep the condensate from freezing when ambient temperatureconditions are below freezing.
 8. The air conditioning unit of claim 7further comprising a vertical standpipe having a larger cross-sectionaldimension than the low path, wherein the low path discharges into thevertical standpipe and the condensate is allowed to drip into thevertical standpipe while the minority of the combustion gasses emergingfrom the low path are exhausted upward between the low path and thestandpipe.
 9. A method of reducing consumption of fossil fuels andreducing emission of greenhouse gasses from widely used HVAC equipment,the method comprising in any order at least the acts of: manufacturing,obtaining, or providing air conditioning units having condensing gasheat exchangers; advertising that the air conditioning units can beinstalled on a roof of a building and condensate from the condensing gasheat exchangers can be disposed of by routing a drain line through theroof of the building for disposal inside the building; and advertisingthat the air conditioning units can be installed at ground level andcondensate from the condensing gas heat exchangers can be disposed ofinto the ground.
 10. The method of claim 9 wherein the act ofmanufacturing, obtaining, or providing the air conditioning unitscomprises manufacturing, obtaining, or providing air conditioning unitsthat include: a condensing gas heat exchanger having at least one stagethat has fins; a collector connected to the at least one stage that hasfins, wherein the collector comprises a drain line opening penetratingthe collector; and an inducer fan having an inlet connected to thecollector.
 11. The method of claim 10 wherein the act of manufacturing,obtaining, or providing the air conditioning units comprisesmanufacturing, obtaining, or providing air conditioning units thatinclude a drain hole extending through the collector to the inlet of theinducer fan wherein the drain hole is higher than the drain lineopening.
 12. The method of claim 10 further comprising an act ofinstructing an installer of the units that when they install the unit atground level and dispose of condensate from the condensing gas heatexchanger into the ground, that they can leave in place, or install, aplug in the drain line opening penetrating the collector and allow thecondensate to pass through the inducer fan.
 13. The method of claim 10further comprising an act of instructing an installer of the units thatwhen they install the unit on the roof of the building and dispose ofcondensate from the condensing gas heat exchanger in the building, thatthey can leave attached, or attach, the drain line to the openingpenetrating the collector, route the drain line through the roof, andallow the condensate to pass through the drain line for disposal insidethe building.
 14. (canceled)
 15. The method of claim 13 furthercomprising an act of instructing an installer of the units that whenthey install the unit on the roof of the building and dispose ofcondensate from the condensing gas heat exchanger in the building, thatthey can install the unit on a roof curb assembly and route the drainline through a tubular conduit that passes through the roof curbassembly and through the roof of the building.
 16. The method of claim 9further comprising an act of instructing an installer of the units thatwhen they install the unit on the roof of the building and dispose ofcondensate from the condensing gas heat exchanger in the building, thatthey can route the drain line through the roof of the building inside ofa return duct that connects to the unit to deliver air from within thebuilding to the unit.
 17. The method of claim 9 wherein the act ofmanufacturing, obtaining, or providing the air conditioning unitscomprises manufacturing, obtaining, or providing air conditioning unitsthat include a return duct opening for connecting the unit to a returnduct that delivers air to the unit from the building, wherein the drainline is connected to the unit to receive the condensate and the drainline extends to the return duct opening and is stored at the return ductopening during shipment of the unit for routing the drain line throughthe return duct when the unit is installed on the roof of the building.18. The method of claim 9 wherein the act of manufacturing, obtaining,or providing the air conditioning units comprises manufacturing,obtaining, or providing air conditioning units that include a returnduct opening for connecting the unit to a return duct that delivers airto the unit from the building and a tubular conduit that extends to thereturn duct opening for routing the drain line through the return ductwhen the unit is installed on the roof of the building.
 19. The methodof claim 9 further comprising an act of instructing an installer of theunits that when they install the unit at ground level and dispose ofcondensate from the condensing gas heat exchanger into the ground, thatthey can install a bifurcation in an exhaust conduit extending from anoutlet of an inducer fan of the unit to outside of an enclosure for theunit, that the bifurcation can be installed to provide a high path and alow path, and that the low path can be installed to discharge into avertical standpipe.
 20. The method of claim 9 further comprising an actof instructing an installer of the units that when they install the unitat ground level and dispose of condensate from the condensing gas heatexchanger into the ground, that they can provide a low path thatdischarges into a vertical standpipe that extends into the ground andterminates with at least one opening to the ground below a frost line inthe ground.
 21. The method of claim 9 further comprising an act ofinstructing an installer of the units that when they install the unit atground level and dispose of condensate from the condensing gas heatexchanger into the ground, that they can direct the condensate todischarge into a bed of porous alkaline material in the ground toneutralize acidity of the condensate.